Cummins 5.9L and 6.7L Issues and Review of Operations CUMMINS 5.9L and 6.7L ISSUES and REVIEW of OPERATION Presented by Tony Salas Disclaimer of Warranties

LBT 258 Cummins 5.9L and 6.7L Issues and Review Of Operations CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas Disclaimer of Warranties:

This manual contains test procedures and test information obtained by an ASE Certified Master Technician with known good test equipment on real vehicles. Your tests may vary due to your equipment or technician procedures.

No warranty can be made from the ideas presented due to personal testing procedures, nor does the author or anyone connected with him assume responsibilities or liabilities. The use of this manual is conditional on the acceptance of this disclaimer. If the terms of this disclaimer are not acceptable, please return this manual.

Automotive Video, Inc. 6280 Arc Way Ft. Myers, FL 33966 1-800-71-TRAIN (1800-718-7246) fax: 1-239-561-9111 www.auto-video.com

Content authored for Automotive Video Inc. by Heritage Technical LLC, Cochranville, PA. Copyrighted © in 2013 by Automotive Video Inc. No portion of this manual may be copied, altered, or reproduced without written permission of the author. TABLE OF CONTENTS

USE OF OEM SERVICE INFORMATION ...... 2 CHARGE AIR COOL (CAC) SYSTEM ...... 38 USE OF OEM SCAN TOOLS ...... 4 ELECTRONICALLY CONTROLLED ACTUATOR ...... 39 READING SKIM CODES ...... 4 TURBOCHARGER HANDS ON AND RECAP ...... 40 UNDERSTANDING BODY CODES ...... 5 TURBOCHARGER EXHAUST BRAKE FUNCTION ...... 40 THE 6.7L REPLACES THE 5.9L ...... 6 TURBOCHARGER COOL DOWN ...... 41 EMISSION STANDARDS ...... 6 TURBOCHARGER COOL DOWN CHART ...... 41 SELECTIVE CATALYST REDUCTION ...... 8 VGT POWER INPUT ...... 42 THE AFTERTREATMENT SYSTEM (DOC & DPF) ...... 9 ACTUATOR COOLANT PASSAGE ...... 42 REGENERATION ...... 11 VGT SCAN TOOL DATA ...... 43 DOC SENSORS AND RELATED ISSUES ...... 13 WITECH® SCAN TOOL ...... 44 OXYGEN SENSOR ...... 13 LAUNCHING THE DRB EMULATOR ...... 44 DIFFERENTIAL PRESSURE SENSOR ...... 14 WITECH® VEHICLE VIEW ...... 45 EXHAUST GAS TEMPERATURE SENSOR ...... 14 WITECH® MODULE VIEW ...... 45 TURBO DOWN PIPE ...... 15 SAMPLE TECHNICAL SERVICE BULLETIN (TSB) ...... 47 VEHICLE DRIVING CONDITIONS AND RELATED ISSUES ...... 15 WITECH ® SCAN TOOL PCM VIEW ...... 50 DOC & DPF SCAN DATA ...... 16 WITECH® SCAN TOOL (MISCELLANEOUS FUNCTIONS) ...... 51 COMPARING THE 5.9L & 6.7L ...... 17 INJECTOR QUANTITY ADJUSTMENTS (IQA) ...... 51 6.7L SPECIFICATIONS ...... 18 IQA CODES ...... 51 5.9L SPECIFICATIONS ...... 19 STATIONARY DESOOT ...... 52 COMMON RAIL FUEL INJECTION SYSTEM ...... 19 TIPM MODULE ...... 52 FUEL INJECTORS ...... 21 WITECH® WCM ...... 54 6.7L FUEL INJECTOR VARIATION ...... 22 WITECH® DTC ...... 56 INJECTOR WIRING ...... 23 SAMPLE DIAGNOSTIC PINPOINT TEST ...... 56 TOTALLY INTEGRATED POWER MODULE (TIPM) ...... 25 WITECH® UTILITIES AND REPORTS ...... 61 FUEL LEVEL SENSOR AND FUEL LEVEL SENSOR MONITOR ...... 26 WITECH® UTILITIES AND REPORTS FUEL FILTER BREAKDOWN ...... 27 (VEHICLE SCAN REPORT) ...... 63 WATER IN FUEL (WIF) DATA ...... 28 STARMOBILE® SCAN TOOL ...... 64 DIAGNOSIS OF THE COMMON RAIL FUEL APPLICATION CHARTS ...... 65 INJECTION SYSTEM ...... 28 WITECH® DIAGNOSTICS - MASS AIR FLOW ...... 68 REBUILT INJECTORS ...... 29 RESETTING THE OIL CHANGE LIGHT WITHOUT A SCAN TOOL . . . .69 BALANCE TESTING ...... 30 RESETTING THE DRIVER INFORMATION CENTER THE EGR SYSTEM ...... 32 WITHOUT A SCAN TOOL ...... 70 EGR AIRFLOW THROTTLE CONTROL VALVE ...... 34 CUMMINS 5.9L STARMOBILE® ...... 70 D1/DH EGR BYPASS VALVE ...... 35 CUMMINS 5.9L CYLINDER TEST ...... 74 CLOSED CRANKCASE VENTILATION (CCV) SYSTEM ...... 35 CUMMINS 5.9L INJECTOR KILL TEST ...... 75 THE TURBOCHARGER ...... 37 CUMMINS 5.9L PRESSURE OVERRIDE TEST ...... 76

1 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

TABLE OF CONTENTS (continued)

SAMPLE TEST PROCEDURE ...... 76 ECM INJECTOR CONTROL ...... 88 CUMMINS 5.9L HIGH PRESSURE FUEL PUMP ...... 79 HIGH PRESSURE FUEL LINE LEAK TESTING ...... 88 CUMMINS 5.9L CASCADE OVERFLOW VALVE ...... 80 FUEL LINE LEAK TEST SAMPLE ...... 88 CUMMINS 5.9L FCA ...... 80 DIAGNOSIS OF THE COMMON RAIL COMMON RAIL EXPLAINED ...... 82 INJECTION SYSTEM (RECAP) ...... 89 FUEL RAIL PRESSURE SENSOR ...... 85 UPDATING THE PCM MODULE REFLASH ...... 90 FUEL PRESSURE LIMITING VALVE ...... 85 IN CONCLUSION ...... 96 PRESSURE LIMITING VALVE TEST SAMPLE ...... 86 APPENDIX ...... 97 INJECTOR OPERATIONS ...... 87 2007 5.9L GENERAL DESCRIPTION ...... 97 AIR CHECK ...... 87 2010 6.7L GENERAL DESCRIPTION ...... 98

USE OF OEM SERVICE INFORMATION

Proper use of service information is critical to diagnosing and repairing vehicles equipped with either the 5.9L or 6.7L Cummins engine. Service information can and should include the OEM factory sites available to you, the technician.

Yes, there are many aftermarket websites that offer diagnostic and service information for these vehicles, but the best option is to use the OEM technical site. Not only will the OEM technical site give you access to diagnostic and repair information, it will also give you access to Technical Service Bulletins (TSBs) and wiring diagrams. Also, if you have access to the factory scan tool, you will have the ability to re-flash modules on the vehicle.

Believe it or not, the ability to re-flash control modules within the vehicle is CRITICAL to successfully repairing issues that are common to the 5.9L and 6.7L Cummins engines. Time and time again we have seen trucks come into the shop and after reviewing the applicable TSBs, the solution to the problem was either an update to a module or, on the 6.7L Cummins, an update was available for the injectors which are programmable.

2 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

USE OF OEM SERVICE INFORMATION

For Chrysler, there are two websites available for a nominal subscription fee. For the aftermarket technician there is https://www.techauthority.com/en-US/Pages/Home.aspx . For dealerships there is https://dealerconnect.chrysler.com/

NOTES

3 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

USE OF OEM SCAN TOOLS

READING SKIM CODES

As mentioned earlier, the Sentry Key Immobilizer Module (SKIM) is an integral part of the Sentry Key Immobilizer System (SKIS). The Sentry Key Immobilizer System (SKIS) provides passive vehicle protection by preventing the engine from operating unless a valid electronically encoded key is detected in the ignition lock cylinder.

The SKIS used in combination with the export premium version of the VTSS adds a steering shaft lock feature that provides passive protection by preventing the vehicle from being steered unless a valid electronically encoded key is detected in the ignition lock cylinder.

The SKIS includes the following major components:

Powertrain Control Module - The Powertrain Control Module (PCM) is located in the engine compartment.

Security Indicator - A security indicator is integral to the Electro Mechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN).

Sentry Key Remote Entry Module/Wireless Ignition Node (WIN) - The WIN located on the right side of the steering column concealed beneath the instrument panel.

Sentry Key Transponder - The Sentry Key transponder is contained within the Remote Keyless Entry (RKE) transmitter on the ignition key.

All newer trucks, 2002 and up, require a SKIM code to flash or re-flash any control module. Once you have connected the SKIM reader to the vehicle you will have the option to read the SKIM code BEFORE you flash or re-flash any of the vehicles control modules. You will also have the options to read and clear DTCs as well as erase and program ignition keys.

4 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

UNDERSTANDING BODY CODES

The Vehicle Identification Number (VIN) plate (2) is located on the lower windshield fence near the left a-pillar. The VIN contains 17 characters that provide data concerning the vehicle. Refer to the VIN decoding chart to determine the identification of a vehicle.

The VIN is also imprinted on the: 1. Body Code Plate. 2. Equipment Identification Plate. 3. Vehicle Safety Certification Label. 4. Frame rail.

To protect the consumer from theft and possible fraud the manufacturer is required to include a Check Digit at the ninth position of the VIN. The check digit is used by the manufacturer and government agencies to verify the authenticity of the vehicle and official documentation. The formula to use the check digit is not released to the general public.

If you are using the OE scan tool, the body codes will be available to view on the screen. The most common trucks you will see in your shop will have the following body codes.

DC – Dodge Heavy Duty Chassis Cab (2007 and up). DH & D1 – Dodge Ram Pickup HD (Heavy Duty) (2006 and up). DR – Ram Truck.

5 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE 6.7L REPLACES THE 5.9L

In 2007 the 6.7L Cummins engine replaced the 5.9L Cummins engine. The 6.7L engine is designed to meet the 2007 emission requirements but it also set the stage to meet the 2010 emission requirements as well.

The 6.7L is the latest version of the B Series Cummins Diesel Engine. It is currently the largest straight-six engine produced for a light duty truck. It produces 350 – 400 horsepower and 650 pound-feet of torque in the 2007.5 and newer Dodge 2500/3500 pickup trucks with the Chrysler-built six-speed 68RFE automatic transmission built at the Kokomo Transmission plant in Kokomo, Indiana. Engine torque is slightly reduced with the Mercedes G56 6-speed manual transmission at 350 horsepower and 610 pound-feet of torque. The 2007 and newer 3500 Cab & Chassis trucks only get the 305 horsepower and 610 pound-feet of torque version of the 6.7L, whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission.

As for the 2008 and newer 4500/5500 medium duty Chassis Cabs or the Sterling Bullet Trucks, they will also receive the 305 horsepower and 610 pound-feet of torque version of the 6.7L, whether it has the Aisin AS68RC or the Mercedes G56 6-speed manual transmission.

Late model 2011 Ram trucks produce 350 horsepower and 800 pound-feet of torque, with the exhaust brake rating boosted from 150 horsepower to 222 horsepower.

EMISSION STANDARDS

Diesel engines are used worldwide because they achieve better fuel economy, lower carbon dioxide (CO2) emissions and produce higher levels of power than conventional gasoline engines. However, diesel engines tend to be more costly and emit high levels of oxides of nitrogen (NOx) and particulate matter (PM) emissions. While several technology options exist to decrease these emissions, the U.S. Environmental Protection Agency (EPA) and industry partners are evaluating and developing EPA’s Clean Diesel Combustion (CDC) technology, which refines several existing technologies into a unique engine design that is simultaneously clean, efficient, and cost effective.

As you begin to see vehicles equipped with the 6.7L engine enter your shop, you are going to notice right away that this engine is equipped with MANY more emission controls than the 5.9L. This move towards a cleaner burning diesel engine was driven by the EPA emission requirements. This legislation has imposed the drastic reduction of emissions on diesel applications. This new standard is calling for more than a 90% reduction in NOx emissions and Particulate Matter (PM).

EPA emission standards – both 2007 heavy-duty engine and the Tier 2 standards for passenger vehicles call for major reductions (ranging from 77 to 95 percent) in NOx and PM emissions. Although several methods are being examined to meet these future standards, today’s primary path option to reduce diesel NOx emissions is through the use of aftertreatment devices. NOx aftertreatment devices control emissions downstream from the engine’s combustion chamber, in the exhaust system rather than in the engine.

6 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

EMISSION STANDARDS

What is Clean Diesel Combustion? The method of CDC encompasses a series of design changes to the diesel engine, which decrease NOx emissions while maintaining or improving engine efficiency. The key concept of CDC technology is the development of in-cylinder NOx control, where NOx emissions are reduced in the engine combustion chamber without penalizing the engine’s efficiency. Preliminary EPA research has demonstrated positive results for a design that achieves in-cylinder NOx emissions much lower than levels reported by industry.

Key Features of CDC Technology • EPA Fuel System – Uses a hydraulically intensified fuel system to lower PM and smoke emissions, and improve engine efficiency. • Boost System – Increases the engine power and the efficiency of the combustion process, thus reducing emissions and increasing fuel economy. • Low Pressure Exhaust Gas Recirculation (EGR) – Lowers the peak combustion temperature to reduce the formation of NOx. • PM Aftertreatment – Reduces the remaining smoke, unburned hydrocarbons (HC) and carbon monoxide in the exhaust to levels required for future emissions standards.

Benefits of CDC CDC, with its unique combination of technology advances, offers benefits such as: • Low Cost – In-cylinder NOx control (where NOx emissions are reduced in the engine combustion chamber) greatly simplifies the aftertreatment system requirements (conventional aftertreatment to reduce smoke, PM, and HC). • Low Emissions – Potential to achieve levels of 2007/2010 Heavy-Duty Engine and Tier 2 emission standards without the use of NOx aftertreatment. • Scalable – Applicable to both light-duty and heavy-duty diesel engines.

7 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

SELECTIVE CATALYST REDUCTION

New for 2013 and some 2012 models is the use of a system called Selective Catalytic Reduction (SCR). SCR is a method of converting harmful diesel oxides of nitrogen (NOx) emissions, by catalytic reaction, into benign nitrogen gas and water. SCR can deliver near-zero emissions of NOx, an acid rain and smog-causing pollutant and greenhouse gas, in modern highway clean diesel engines.

The SCR system does not alter the design of the modern Common Rail Diesel (CRD) engine; therefore it can continue to deliver excellent fuel economy and durability. Rather, SCR provides emissions after-treatment well into the exhaust stack, in a way similar to the soot containment achieved by the Diesel Particulate Filter (DPF).

SCR works by injecting Diesel Exhaust Fluid (DEF), such as AdBlue, into the hot exhaust stack. DEF works in conjunction with the hot exhaust gases and catalyst to break NOx into two components of our normal atmosphere—water vapor and nitrogen.

The Process - How SCR Works Engine: The NOx reduction process starts with an efficient CRD engine design that burns clean Ultra Low Sulfur Diesel (ULSD) and produces inherently lower exhaust emissions—exhaust that is already much cleaner due to leaner and more complete combustion.

Diesel Exhaust Fluid (DEF) tank and pump: Under the direction of the vehicle’s onboard computer, DEF is delivered in precisely metered spray patterns into the exhaust stream just ahead of the SCR converter.

SCR Catalytic Converter: This is where the conversion happens. Exhaust gases and an atomized mist of DEF enter the converter simultaneously. Together with the catalyst inside the converter, the mixture undergoes a chemical reaction that produces nitrogen gas and water vapor.

Control device: Exhaust gases are monitored via a sensor as they leave the SCR catalyst. Feedback is supplied to the main computer to alter the DEF flow if NOx levels fluctuate beyond acceptable parameters.

8 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE AFTERTREATMENT SYSTEM (DOC & DPF)

The Aftertreatment System consists of three catalyst elements, all working together to drastically reduce tailpipe emissions.

DIESEL OXIDATION CATALYST (DOC) The Diesel Oxidation Catalyst (DOC) is a ceramic flow through substrate coated with a catalyst washcoat that is integral to the DOC assembly. The close coupled DOC treats engine exhaust gases by converting harmful carbon monoxide, unburned hydrocarbons and other compounds into water, carbon dioxide and heat.

Pick-up vehicles use a separate DOC assembly.Cab-Chassis vehicles use a combination Diesel Oxidation Catalyst/Diesel Particulate Filter (DOC/DPF)

CLOSE COUPLED CATALYST (CCC) The CCC is basically a diesel oxidation catalyst (DOC) that is mounted very close to the turbocharger exhaust outlet. It is a metallic flow through substrate coated with a catalyst washcoat that is essential to the integrated operation of the aftertreatment assembly. The close coupled DOC treats engine exhaust gases by converting harmful carbon monoxide, unburned hydrocarbons and other compounds into water, carbon dioxide and heat. The ability to create heat is an important part of the system regeneration process.

NOx ABSORBER CATALYST (NAC) The NAC is located downstream of the CCC. Using the heat and exhaust constituents coming from the CCC, the NAC traps various oxides of nitrogen, and then converts those into Carbon Dioxide, Nitrogen (N2) and water via a regeneration process controlled by the engine's electronic control module (ECM). The NAC also plays a role in reducing non-methane hydrocarbons (NMHC) from the exhaust gas.

The NAC is located downstream of the CCC. Using the heat and exhaust constituents coming from the CCC, the NAC traps various oxides of nitrogen, and then converts those into Carbon Dioxide, Nitrogen (N2) and water

9 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE AFTERTREATMENT SYSTEM (DOC & DPF) via a regeneration process controlled by the engine's electronic control module (ECM). The NAC also plays a role in reducing non-methane hydrocarbons (NMHC) from the exhaust gas.

DIESEL PARTICULATE FILTER (DPF) The diesel particulate filter (DPF) is a wall-pass ceramic filter substrate coated with a catalyst washcoat. It is located just downstream of the NAC. Exhaust gases flow from the NAC into the catalyzed diesel particulate filter (DPF) which traps and accumulates particulate matter, and further treats the exhaust gases to reduce any remaining unburned hydrocarbons and other harmful compounds. The trapped particulate matter will be periodically removed from the DPF via a regeneration process controlled by the engine’s electronic control module (ECM).

SYSTEM OPERATION The oxidation catalyst raises the exhaust gas temperatures to regenerate the DPF, which is passive regeneration. If the passive regeneration cannot keep up with the buildup of soot in the DPF, the ECM will actively regenerate the DPF to burn off the soot. Residue remains inside the DPF in the form of non burnable ash. Ash comes from the oils and other materials that are trapped in the oils and are present in the soot.

The catalyst contains a large number of parallel channels, which run in the axial direction and are separated by thin porous walls. The channels are alternatively open at one end, but plugged at the other. The exhaust gases flow through the walls and escape through the pores in the wall material. Particulates, however, are too large to escape and are trapped in the monolith walls.

The ECM starts the regeneration of the DPF if the soot load exceeds a performance MAP value. The ECM determines the load condition of the DPF based upon the exhaust gas pressure upstream and downstream of the DPC/DPF. A pressure differential sensor provides the pressure input to the ECM.

During the regeneration process, the ECM raises the temperature in the DOC/DPF to burn off the soot accumulated. Under normal operation, the engine does not produce enough heat to oxidize the soot inside the DOC/DPF. This process requires temperatures above 550 ºC (1,022 ºF). After regeneration, the ECM reads the actual pressure difference at the DOC/DPF and compares it with a reference value. From this comparison, the ECM determines the ash quantity inside the DOC/DPF.

All Diesel Particulate Filters (DPFs) require regular service. Service is required to remove the ash that has accumulated inside the DPF. A poorly maintained DPF can result in exhaust back pressure that will lead to increased regeneration times, loss of horsepower, reduced fuel economy, filter damage, and ultimately engine damage. It is important that all on road fleet owners create a DPF Maintenance Program. Regularly scheduled filter cleaning will save you time and money by reducing the need for DPF repairs and/or truck downtime for additional maintenance.

10 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

REGENERATION

You may have noticed if you have one the 07+ diesel pickups that it never puts out any black smoke at all. The DPF will capture 90% or better of all harmful diesel emissions. Once the DPF has become "full" of soot, it will need to have a regeneration cycle in order to burn all the soot out. You may have noticed a light on your dash from time to time that alerts you that the DPF is in "regen" or "cleaning filter."

Basically what is happening during this process is that the engine's computer has decided from the information that it receives from the sensors installed in the exhaust that the DPF has filled up past its acceptable limit. The computer then opens the EGR (exhaust recirculation valve) introducing hot exhaust into the intake to help get exhaust gas temps higher and also injects a small shot of fuel into the cylinders when the exhaust valves are open.

The raised exhaust temps and the small amount of fuel then burn out the particulate (soot) that the DPF has collected since its last regen. Once the computer gets readings from the sensors in the exhaust that the filter is passing exhaust gas an acceptable limit again, it ends the regen cycle. The frequency of this cleaning cycle is different from vehicle to vehicle depending on use, mileage, and engine condition.

Common problems with the DPF system:

1. Poor Fuel economy - This is the number one complaint we get from customers who have trucks equipped with a DPF. Most customers who traded in their pre-07 diesel pickups have been completely unhappy with the lack of fuel mileage that they used to enjoy. The average fuel economy we hear people report on DPF equipped trucks is usually 12-14 mpg. Many of these folks traded in trucks that did 18-22 mpg and are completely disgusted.

2. Excessive regens - Many of our customers who use their trucks for work complain about very frequent regens that kill their fuel mileage and performance. Many customers who work outdoors in the winter were used to letting their old diesels run all day while they were on the job site. The DPF equipped trucks don't handle this very well. The cooler idling temperature of the exhaust gas will soot up the DPF on an accelerated rate. It is not uncommon for these customers to be on their second or third filter change because the truck went into constant limp mode. The usual dealership response is: "You can't let these new trucks idle."

3. High replacement cost - A replacement DPF (which isn't available aftermarket yet) runs roughly $2000-$2600 for the just the filter alone.

What can be done to extend DPF life and limit regens?

Since we are not allowed by law to remove the DPF system, we are stuck with it if you want to comply with Federal emissions and keep your truck legal. Here are a few tips to help mileage and DPF life: 1. Use the right fuel - It is absolutely crucial and necessary to use ultra low sulphur fuel in any vehicle equipped with a particulate filter. High amounts of sulfur in the fuel will plug the DPF immediately.

2. Use the proper engine oil - Make sure you are using engine oil that is rated properly for your truck. Some engine oil gets burnt up in combustion no matter what. If you are running oil that is not formulated for a DPF equipped vehicle, it will soot up the filter sooner.

3. Keep idling to a minimum - Simply put, idling contributes to DPF problems.

4. Run it hard once in a while - Don't be afraid once in a while when going up a hill to press the accelerator pedal to the floor for a few seconds. Running the truck hard and getting things nice and warm will help clear out soot deposits.

11 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

REGENERATION

I want to remove the DPF. What can I do and what will be the benefits? First thing, it is absolutely against the law to remove or disable any emissions device for any vehicle that is going to be operated on the public highways. If you decide you want to remove emissions equipment for any reason, it is solely up to you and your mechanic to decide what is safe and legal for your application.

Passive Regeneration Passive regeneration is an automated regeneration which often occurs on drives where there is prolonged high exhaust temperatures like for example on motorway-type runs, but it can't be said that all cars get the required long journey motorway-type trips necessary to complete a passive regeneration of the DPF system and so manufacturers have had to adapt the technology and design-in an "active" regeneration process controlled by the Engine Management Computer also known as the Engine Control Module (ECM).

Active Regeneration When the diesel particulate (soot) loading in the diesel particulate filter (DPF) reaches a pre-set limit, the ECM will make minor adjustments to the fuel injection timing system which will in turn increase the exhaust temperatures and help initiate the DPF regeneration process. This is a smart way of getting a motorway-type temperature to build up inside the DPF system and begin a full regeneration to bring the unit back to good health. However, if the journey is a bit stop/start, like in city traffic, then the chances are the regeneration will not complete and eventually the DPF light will illuminate on the dash to tell you that the DPF system is partially blocked.

If you do not do this and choose to ignore the light, it may go out but come back on and as you continue in a relatively slow, stop/start pattern of driving the soot loading will continue to build up and clog up the DPF system until it reaches closer to 75% blocked at which point you can expect other more serious warning lights to appear on the dashboard. By now, driving at speed alone will no longer be sufficient and the vehicle will need to go to a specialized garage or a dealership for regeneration. The other lights may be the engine management light constantly on & possibly even the glow plug light blinking constantly. It is not advised to continue driving the vehicle under these conditions to avoid further costly damages to the DPF system and other mechanical components.

Manual Regeneration Manual regeneration is essentially the same as active regeneration however it is typically initiated using a diagnostic tool by a technician for service or diagnostic purposes. Some manufactures of medium and heavy duty trucks will allow a driver to manually disable regeneration if conditions are not favorable. These vehicles are equipped with a disable switch and some will also have a force regen switch to manually initiate regeneration when certain conditions are met.

12 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DOC SENSORS AND RELATED ISSUES

OXYGEN SENSOR

Two different six-wire Oxygen (O2) Sensors are used. These sensors are upstream and downstream. These (O2) sensors are located on each end of the No. 2 catalyst.

The engine aftertreatment system monitors the O2 content in the diesel engine exhaust. The Powertrain Control Module (PCM) monitors the exhaust gases for oxygen content and varies the rich/lean fuel mixture of the intake air fuel mixture to adjust the system. This diagnostic routine monitors the status message broadcast by the O2 Sensor Module for the upstream O2 sensor’s internal heater circuit.

The PCM will set the fault if it receives a FMI (Failure Mode Indicator) message from the O2 Sensor Module. The PCM will illuminate the MIL lamp immediately when the diagnostic runs and fails. The PCM will turn off the MIL lamp when the diagnostic runs and passes in four consecutive drive cycles.

NOTES

13 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DOC SENSORS AND RELATED ISSUES

DIFFERENTIAL PRESSURE SENSOR

The Exhaust Differential Pressure Sensor is remotely mounted on the transmission housing. Two pressure tubes measure pressure before and after the Diesel Particulate Filter (DPF)/Diesel Oxidation Catalyst (DOC).

The sensor is critical for fail-safe of regeneration strategy, because it interprets high pressure drops as possible high soot loads.

EXHAUST GAS TEMPERATURE SENSOR

The Diesel Exhaust Temperature Sensors are thermistors and change resistance based on the temperature being measured. The Engine Control Module (ECM) provides a 5 volt reference voltage to the sensor. The ECM monitors the change in signal voltage and converts this to a temperature value.

When the exhaust gas temperature is cold, the sensor resistance is high, the Engine Control Module (ECM) will sense the resistance and sense the exhaust temperature as cold.

When the exhaust gas temperature is high, the sensor resistance is low, the ECM will sense the resistance and sense the exhaust temperature as high.

14 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DOC SENSORS AND RELATED ISSUES

TURBO DOWN PIPE

The turbo down pipe is a critical component to the operation of the DOC. This down pipe is double wall insulated to retain as much heat as possible in order to get the DOC up to normal operating temperature. Heat loss must be kept to a minimum in order for the aftertreatment system to operate properly.

This retention of heat is needed in order for the DOC to reach what is known as “Light Off Temperature”. Light off temperature is the temperature needed to ensure the catalyst will work efficiently.

VEHICLE DRIVING CONDITIONS AND RELATED ISSUES

The driving conditions and maintenance of the vehicle will also cause issues and problems concerning regeneration. These regeneration issues occur if the vehicle is poorly maintained, such as extending the oil change interval, or even the use of fuel with poor quality. Another contributing factor to regeneration issues is long idling time common among fleet vehicles such as ambulance or emergency vehicles.

It is important to stress to your customers NOT to ignore the warning light indicating the vehicle needs to have a regeneration event occur. By the time the message is illuminated on the dash requesting a regeneration event, it could mean the PCM has attempted to run regeneration both passively and actively and has failed. Continuing to run the vehicle without a manual regeneration can and will cause the DPF to become overloaded with particulate matter. Once the DPF becomes overloaded, you run the risk of having a clogged exhaust system causing driveability problems and possible damage that will be very expensive to repair.

Ambient conditions are another issue that can cause regeneration problems. Vehicles operated in colder climates may not get hot enough to run a passive or active regeneration. In this case as well, manual regenerations will need to be performed to clear the DPF of particulate matter.

Fuel and oil additives are another cause for regeneration issues. A large number of these additives sold today contain high levels of sulphur and other compounds that can actually damage an aftertreatment system. Your best course of action regarding this issue is to call the manufacturer of the fuel or oil additive you intend on using and make sure their product is DOC/DPF friendly.

In the event you have to replace the DPF, you will need to reset what is known as the “soot model” using a scan tool. The soot model is the calculated amount of grams of particulate stored in the DPF. This calculation is performed by the PCM and is used to determine if and when a regeneration event needs to occur.

15 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DOC & DPF SCAN DATA

There are a few scan tool parameters you need to be aware of with regards to DPF regeneration. Pictured above is a screen capture from the StarMOBILE® desktop client. As indicated by the arrow, you can see the Estimated Soot Load Based on Delta Pressure is 34.906 grams. This reading is the calculated amount of soot that has accumulated in the DPF. This calculation is performed by the PCM and is based on sensor inputs and the amount of fuel consumed since the last regeneration. This parameter is a real quick way to determine how much soot is in the DPF after a real hard road test or after a regeneration event.

Take some time to also notice the other parameters shown on in the screen. These other parameters will tell you how long the vehicle has been traveling within different engine loads. These parameters are a good indication of how much “work” the vehicle is doing. Less work or more time spent idling or at a lower engine load could indicate the aftertreatment system is not getting hot enough to burn off the soot in the DPF.

If you plan on working on vehicles with these types of systems, you must have a scan tool that can not only help you determine if the vehicle needs a regeneration event, you also need a scan tool that will enable you to run the event.

16 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMPARING THE 5.9L & 6.7L

Both the 5.9L and the 6.7L engines have a computer controlled, common rail injection system and turbochargers. Other than fuel quality, that is where the commonalities end. The 5.9L engine has none of the emission control systems the 6.7L has. The 6.7L engine is equipped with an EGR system and cooler, crankcase ventilation (CCV) and the DOC/DPF.

One thing these engines do have in common is the need for good, clean, ultra low sulphur content diesel fuel to operate correctly. As of September 2007, most on-highway diesel fuel sold at retail locations in the United States is ULSD.

Ultra-low-sulfur diesel fuel was proposed by EPA as a new standard for the sulfur content in on-road diesel fuel sold in the United States since October 15, 2006, except for rural Alaska who transferred in 2010. California has required it since September 1, 2006. Since December 1, 2010, all highway diesel fuel has been ULSD. After December 1, 2014 all highway, non-road, locomotive and marine diesel fuel produced and imported will be ULSD. The EPA mandated the use of ULSD fuel in model year 2007 and newer highway diesel fuel engines equipped with advanced emission control systems that require the new fuel.

The allowable sulfur content for ULSD (15 ppm) is much lower than the previous U.S. on-highway standard for low sulfur diesel (LSD, 500 ppm) which allows advanced emission control systems to be fitted that would otherwise be poisoned by these compounds. These systems can greatly reduce emissions of oxides of nitrogen and particulate matter.

Additionally, the EPA is assisting manufacturers with the transition to tougher emissions regulations by loosening them for model year 2007 to 2010 light-duty diesel engines.[9] As a result, Honda, Nissan, Subaru, Toyota, and others are expecting to begin producing diesel vehicles for the U.S. market to join those from Mercedes-Benz, Audi, Volkswagen, and BMW.[10]

According to EPA estimates, with the implementation of the new fuel standards for diesel, nitrogen oxide emissions will be reduced by 2.6 million tons each year and soot or particulate matter will be reduced by 110,000 tons a year.

Sulfur is not a lubricant in of itself, but it can combine with the nickel content in many metal alloys to form a low melting point eutectic alloy that can increase lubricity. The process used to reduce the sulfur also reduces the fuel's lubricating properties. Lubricity is a measure of the fuel's ability to lubricate and protect the various parts of the engine's fuel injection system from wear. The processing required to reduce sulfur to 15 ppm also removes naturally-occurring lubricity agents in diesel fuel.

Biodiesel is an alternative fuel produced from renewable resources, such as soybeans or used restaurant grease. Biodiesel contains no petroleum, but it can be blended with petroleum diesel to create a biodiesel blend. It can be used in diesel engines with no major modifications. Biodiesel is simple to use, biodegradable, nontoxic, and essentially free of sulfur and aromatics.

Biodiesel can be used as a pure fuel or blended with petroleum in any percentage. B20 (a blend of 20 percent by volume biodiesel with 80 percent by volume petroleum diesel), B2, and B5 are common fuel blends used today. Biodiesel is registered as a fuel and fuel additive with the U.S. Environmental Protection Agency (EPA) and meets clean diesel standards established by the California Air Resources Board (ARB). Neat (100 percent) biodiesel has been designated as an alternative fuel by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation (DOT).

17 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMPARING THE 5.9L & 6.7L

Early in 2011, Cummins announced an upgraded version of the 6.7L Cummins would be released for the spring. The updated engine saw torque increase to 800 lb-ft (from 650 lb-ft). Horsepower ratings did not change, nor did output for the de-rated, manual transmission version of the engine.

For 2013, the 6.7L Cummins underwent further changes and was scheduled to be offered in 3 versions: • 350 hp, 660 lb-ft version coupled to the G56 manual trans. • 370 hp, 800 lb-ft version coupled to the 68RFE automatic trans. • H.O. 385 hp, 850 lb-ft version coupled to the Aisin AS69RC trans (High Output).

In addition to the new offerings, SCR (selective catalytic reduction) w/ DEF injection became standard on the new high output version. Ram Trucks reported an approximate 10% increase in fuel economy with the new engine lineup. To reach and safely maintain these power levels, Ram trucks received dual transmission coolers, dual radiators, a higher efficiency intercooler (charge-air-cooler), larger capacity EGR system, and a higher efficiency mechanical fan.

18 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMPARING THE 5.9L & 6.7L

COMMON RAIL FUEL INJECTION SYSTEM

Both the 5.9L and 6.7L engines use a common rail injection system. In a common rail injection system, the fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure fuel is then accumulated in the fuel rail. High pressure fuel is constantly supplied to the injectors by the fuel rail. The Engine Control Module (ECM) controls the fueling and timing of the engine by actuating the injectors.

19 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMMON RAIL FUEL INJECTION SYSTEM

Fuel enters the system from the electric fuel transfer (lift) pump, which is located inside of the fuel tank and attached to the fuel tank module (the fuel transfer pump is no longer attached to the engine). Fuel is forced through the fuel filter element and then enters the Fuel Pump/Gear Pump, which is attached to the rear of the fuel injection pump. The Fuel Pump/Gear Pump is a low-pressure pump and produce pressures ranging from 551.5 kpa (80 psi) to 1241 kpa (180) psi. Fuel then enters the fuel injection pump. Low pressure fuel is then supplied to the FCA (Fuel Control Actuator).

The FCA is an electronically controlled solenoid valve. The ECM controls the amount of fuel that enters the high- pressure pumping chambers by opening and closing the FCA based on a demanded fuel pressure. The FPS (Fuel Pressure Sensor) on the fuel rail monitors the actual fuel pressure and provides it as an input to the ECM. When the actuator is opened, the maximum amount of fuel is being supplied to the fuel injection pump. Any fuel that does not enter the injection pump is directed to the overflow valve. The overflow valve regulates how much excess fuel is used for lubrication of the pump and how much is returned to the tank through the drain manifold.

Fuel entering the injection pump is pressurized to between 200-1800 bar (2900-26107 psi) by three radial pumping chambers. The pressurized fuel is then supplied to the fuel rail.

WARNING! High-pressure fuel lines deliver diesel fuel under extreme pressure from the injection pump to the fuel injectors. This may be as high as 180,000 kpa (26,107 psi). Use extreme caution when inspecting for high-pressure fuel leaks. Inspect for high-pressure fuel leaks with a sheet of cardboard. High fuel injection pressure can cause personal injury if contact is made with the skin.

20 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL INJECTORS

Six individual, solenoid actuated high-pressure fuel injectors are used. The injectors are vertically mounted into a bored hole in the top of the cylinder head. This bored hole is located between the intake/exhaust valves.

High-pressure connectors, mounted into the side of the cylinder head, connect each fuel injector to each high- pressure fuel line. The injector part number is laser-burned onto the injector. Failure to replace with the proper injector will cause severe engine damage.

High-pressure fuel is supplied from the injection pump, through a high-pressure fuel line, into a fuel rail, through high-pressure lines, through steel connectors and into the solenoid actuated fuel injector. The ECM actuates the solenoid causing the needle valve to rise and fuel flows through the spray holes in the nozzle tip into the combustion chamber.

Each fuel injector is connected to the fuel rail by a high-pressure fuel line and a steel connector. This steel connector is positioned into the cylinder head and sealed with an O-ring. The connector is retained in the cylinder head by a nut (fitting) that is threaded into the cylinder head.

The torquing force of this threaded nut (fitting) provides a sealing pressure between the fuel line connector and the fuel injector. Retaining nut torque is very critical. If the nut (fitting) is under torqued, the mating surfaces will not seal and a high-pressure fuel leak will result. If the fitting is over torqued, the connector and injector will deform and also cause a high-pressure fuel leak. This leak will be inside the cylinder head and will not be visible. The result will be a possible fuel injector miss-fire and low power, or a no-start condition.

The fuel injectors use hole type nozzles. High-pressure flows into the side of the injector, the ECM activates the solenoid causing the injector needle to lift and fuel to be injected. The clearances in the nozzle bore are extremely small and any dirt or contaminant's will cause the injector to stick. Because of this, it is very important to do a thorough cleaning of any lines before opening up any fuel system component. Always cover or cap any open fuel connections before a fuel system repair is performed.

21 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL INJECTORS

Each fuel injector connector tube contains an edge filter that is designed to break up small contaminant's before entering the fuel injector. The edge filters are not a substitute for proper cleaning and covering of all fuel system components during repair.

The bottom of each fuel injector is sealed to the cylinder head with a 1.5mm thick copper shim (gasket). The correct thickness shim must always be re-installed after removing an injector.

Fuel pressure in the injector circuit decreases after injection. The injector needle valve is immediately closed and fuel flow into the combustion chamber is stopped. Exhaust gases are prevented from entering the injector nozzle by the needle valve.

6.7L VARIATION Each fuel injector has a six-digit alphanumeric correction code. The correction code is printed on the intake side of the fuel injector (1) and is used to identify injector calibration. When replacing any fuel injectors, this code must be entered into the vehicles Powertrain Control Module (PCM) using a diagnostic scan tool. In addition, if a new PCM is installed, use a diagnostic scan tool to program all six of the injector codes from the original fuel injectors into the new PCM.

The valve cover and valve cover gasket will need to be removed in order to manually record the values from the original injectors. Contact cleaner or brake cleaner may be used to clean the fuel injector.

NOTES

22 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

INJECTOR WIRING

Although the 5.9L and 6.7L injectors are similar, the wiring is quite different. Pictured above is a wiring diagram for injectors 6, 5 and 4 on a Cummins 5.9L engine. What is important to notice is the injectors are wired as a group and in parallel.

Basic electric theory tells us that the total resistance in a parallel circuit is less than any of the individual resistances. Rtotal = 1 / (1/R1 + 1/R2 + . . . 1/Rn). This means, we have three injectors. These injectors have coils and the coils have resistance. Can one shorted coil cause a high enough current to the point that the companion injectors are shut down? The answer is yes.

The computer is equipped with a driver that is thermally protected much like a circuit breaker. Cummins computers do not tolerate this type of cycling due to a short very well. This means if you have a constant P0201- P0206 being set and you do not address it, you will probably end up frying the computer.

A classic example of this would be a customer entering your shop with a vehicle that has a dead injector and a P020X code in the PCM memory. After diagnosis you find the injector itself is fine but the wiring to the injector has the problem.

23 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

INJECTOR WIRING

Pictured above is an injector wiring diagram for injectors 1, 2 and 3 on a Cummins 6.7L engine. As you can see, these injectors are wired in a series circuit and one injector circuit will not affect the others. This corrects the circuit issues that were so problematic on the 5.9L.

If you have been working on vehicles equipped with 5.9L engines long enough, then you are probably familiar with the problems regarding injector wiring harness connectors. This problem also exists with the injector harness connectors on the 6.7L engine. You need to make sure the connections are clean and tight.

You also need to make sure you check the resistance correctly. During a pinpoint test you may find the specification for the injector resistance reading should be between 0-1 Ohm. Before performing this test, zero your meter and compensate for the resistance in your test leads.

24 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

TOTALLY INTEGRATED POWER MODULE (TIPM)

The Totally Integrated Power Module (TIPM) is a combination unit that performs the functions of the Power Distribution Center (PDC) and the Front Control Module. The TIPM is a printed circuit board based module that contains fuses, internal relays and a microprocessor that performs the functions previously executed by the FCM.

The TIPM is located in the engine compartment, next to the battery and connects directly to the B+ cable via a stud located on top of the unit. The ground connection is via electrical connectors. The TIPM provides the primary means of voltage distribution and protection for the entire vehicle.

The molded plastic TIPM housing includes a base and cover. The TIPM cover is easily opened or removed for service and has a fuse and relay layout map integral to the inside surface of the cover. The TIPM housing base and cover are secured in place via mounting tabs. The mounting tabs secure the TIPM to the TIPM mounting bracket.

All of the current from the battery and the generator output enters the Totally Integrated Power Module (TIPM) via a stud on the top of the module. The TIPM cover is removed to access the fuses or relays. Internal connections of all of the power distribution center circuits are accomplished by a combination of bus bars and a printed circuit board.

25 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL LEVEL SENSOR AND FUEL LEVEL SENSOR MONITOR

The fuel gauge sending unit (fuel level sensor) is attached to the fuel pump module. The sending unit consists of a float, an arm, and a variable resistor track (card). The sensor is non-serviceable. If service is necessary, the fuel pump module assembly must be replaced.

The fuel pump module assembly is located on the top of the fuel tank. The complete assembly contains the following components:

* A combination fuel filter/fuel pressure regulator * A separate fuel pick-up, or inlet filter * An electric fuel pump * A lock ring to retain pump module to tank * A soft gasket between tank flange and module * A fuel gauge sending unit (fuel level sensor) * Fuel line connection

If the electrical fuel pump, primary inlet filter, fuel filter or fuel pressure regulator require service, the fuel pump module must be replaced.

The fuel level sensor works differently than a traditional fuel level sending unit. For example, 12 volts is supplied by the battery to the resistor track. When the fuel level is high, the voltage decreases. When the fuel level is low, the voltage increases. The voltages will range from 0.6 volt when the tank is full to 7.0 volts when the tank is empty. It is important to remember the ECM uses this information along with other sensor inputs from the aftertreatment system to calculate the soot model as referenced earlier.

A voltage signal is sent from the resistor track to the ECM. The ECM then interprets the voltage drop and sends a BUS message to the Cabin Compartment Node (CCN), where it is translated into the fuel level gauge reading. There are DTCs that will be set and stored in the PCM that relate to the fuel level sensor when a fault is detected.

* Fuel Level Sensor Circuit High * Fuel Level Sensor Circuit Low * Fuel Level Sensor Performance

26 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL FILTER BREAKDOWN

The fuel filter/water separator assembly is located on the left side of the engine above the starter motor. The assembly also includes the fuel heater, water drain valve, Water-In-Fuel (WIF) sensor. The fuel filter/water separator protects the fuel injection pump by removing water and contaminant's from the fuel. The construction of the filter/separator allows fuel to pass through it, but helps prevent moisture (water) from doing so. Moisture collects at the bottom of the filter.

The OE filter itself is rated at 7 microns. In our opinion, this is not fine enough to filter out all of the contaminant's that could harm a common rail injection system. Common rail injection systems are very sensitive to contaminant's and we recommend a 3-4 micron filter to protect the system. While the OE service information recommends replacing the fuel filter element every 15,000 miles, we recommend replacing the fuel filter element at every oil change or even better, every 5,000 miles.

There are other components within the fuel filter assembly such as the Water In Fuel (WIF) Sensor. The WIF sensor is located on the side of the fuel filter/water separator canister . The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter/water separator.

As the water level in the filter/separator increases, the resistance across the WIF sensor decreases. This decrease in resistance is sent as a signal to the ECM and compared to a high water standard value. Once the value reaches 30 to 40 kilohms, the ECM will activate the water-in-fuel warning lamp through CCD bus circuits. This all takes place when the ignition key is initially put in the ON position. The ECM continues to monitor the input while the engine is running.

Also located on the fuel filter housing is the fuel heater. The fuel heater is used to prevent diesel fuel from waxing during cold weather operation.

When the fuel temperature is below 32° F (0° C), the temperature sensor allows current to flow to the heater element warming the fuel. When the fuel temperature is above 64° F (18° C), the sensor stops current flow to the heater element.

Battery voltage to operate the fuel heater element is supplied from the ignition switch and through a solid state device in the TIPM. The fuel heater element and solid state device in TIPM are not computer controlled. The heater element operates on 12 volts, 300 watts at 0° F (-18° C).

27 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WATER IN FUEL (WIF) DATA

The WIF sensor is located on the side of the fuel filter/water separator canister. The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter/water separator.

The ECM will monitor the WIF sensor and circuit. Faults that can be detected are: * Water in Fuel Sensor Circuit High * Water in Fuel Sensor Circuit Low * Water in Fuel Condition * Water in Fuel Detected for too long

The scan tool parameters available are: * Water in Fuel Voltage (Volts) * Water in Fuel Counts (0 to 2 Counts)

Tech Tip: When working on vehicles equipped with a Cummins 6.7L and you have water in fuel situation, always look at the vent for the fuel tank. There was a bowl on top of the tank where it is possible for the vent tube to lay on and suck water into the fuel system.

DIAGNOSIS OF THE COMMON RAIL INJECTION SYSTEM

Now that we have discussed the various components of the common rail fuel injection system, we can now discuss the diagnostic structure of the system. As you diagnose common rail injection issues, it is important to go step by step.

The first step in our diagnostic procedure is to examine the lift pump pressure. The purpose of the lift pump is to supply (transfer) a low-pressure fuel source: from the fuel tank, through the fuel filter/water separator and to the fuel injection pump. Here, the low-pressure is raised to a high-pressure by the fuel injection pump for operation of the high-pressure fuel injectors. Check valves within the pump control direction of fuel flow and prevent fuel bleed-back during engine shut down.

The transfer pump is self-priming: When the key is first turned on (without cranking engine), the pump will operate for approximately 2 seconds and then shut off (Note: When ambient temperatures are cold enough to cause the intake air heaters to operate, the fuel lift pump will operate during the entire intake air pre-heat cycle). The pump will also operate for up to 25 seconds after the starter is engaged, and then disengaged and the engine is not running. The pump shuts off immediately if the key is on and the engine stops running.

The fuel volume of the transfer pump will always provide more fuel than the fuel injection pump requires. Excess fuel is returned from the injection pump through an overflow valve, and then back to the fuel tank.

When diagnosing a lift pump you need to monitor the lift pump pressure and the lift pump volume. When performing a road test, it is always a good idea to keep the pressure gauge connected so you can view the pressure under different load conditions to determine if the lift pump is responding accordingly.

28 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DIAGNOSIS OF THE COMMON RAIL INJECTION SYSTEM correctly. This is not negotiable. This is another item you would want to view during a road test. You need to see the actual fuel pressure parameter be equal to the desired fuel pressure under different load conditions.

To determine if you have excessive fuel return there is what is known as a “Cap Test”. There are caps being sold in the aftermarket that will let you cap the line going to the fuel rail to eliminate specific injectors. At this point, you can monitor the fuel pressure with your scan tool and see if the pressure rises. This is a nice test to perform but it can sometimes be difficult to determine which injector is bad.

Oil dilution is another issue you need to look for when diagnosing the common rail fuel injection system. If you are working on a 6.7L Cummins that runs excessive post injections due to excessive regeneration events, the engine oil can get diluted. If an injector is the culprit, it’s a good idea to disconnect the FCA or the MPROP, raise the rail pressure high while cranking the engine, and observe the injectors to see if there is any fuel leaking, thus diluting the engine oil.

The point to all of this is to build a structure to your diagnostic strategy. Start with the low pressure side, move to the high pressure side, then on to the return side.

REBUILT INJECTORS

A subject that is becoming increasingly more important is the use of rebuilt or remanufactured fuel injectors. There are a multitude of companies today rebuilding injectors for resale in the 5.9L and 6.7L Cummins applications. Some of these companies are rebuilding these injectors to Bosch® specifications and standards, and some companies are not. There is a need for these rebuilt injectors when you consider the price to replace one can be very expensive, especially with the 6.7L engine. Prices can and will range from $250.00 - $300.00 minimum per injector. This price does not include any diagnostic time or labor time for replacement. When shopping around for rebuilt injectors you need to determine where you are better off buying them. Are you better off buying injectors from Cummins, directly from Bosch® or some other aftermarket vendor?

One important thing to consider when determining which injectors to buy is whether or not the injectors are built to the Bosch® standards and specifications. Bosch® only supplies standards and specifications to Bosch® certified remanufacturing centers. When you see advertising over the internet regarding a special price on injectors, there is no way of telling if the injectors have been remanufactured to the correct specification or not. In short, buyer beware and make sure you do your homework before buying remanufactured injectors.

Testing the injectors function can get a little tricky as well. Some technicians like to remove the injector and bench test it outside of the vehicle while others rely on testing the injector on the vehicle using “real world” conditions. The problem with bench testing common rail injectors is that the bench tester will tell you that you possibly have a bad injector, but it will not tell you if an injector is good. It is our opinion the best place to test an injector is on the vehicle with real world conditions. There are other things to consider such as the quality of the fuel and how well the engine is running but in the case of testing the injectors function, we need to make sure we are testing correctly.

Let’s not forget that one of the tell tale signs of a bad injector is excessive smoke. It is important not to overlook basic engine checks. If you remove the injector, what else can you do at this point to check base engine problems? You can check that cylinders compression. It is not surprising to find that one cylinder has 350 – 360 psi of compression and another cylinder to have 250 – 260 psi. Will this cause the engine to smoke excessively? Probably,

29 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

REBUILT INJECTORS but the result of this compression test across cylinders could eliminate the injector from being the cause of the problem.

When working with the 6.7L Cummins engine we find the injectors being critical because technicians are not programming the correction codes into the PCM after replacement. Each fuel injector has a six-digit alphanumeric correction code. The correction code is printed on the intake side of the fuel injector and is used to identify injector calibration.

When replacing any fuel injectors, this code must be entered into the vehicles Powertrain Control Module (PCM) using a diagnostic scan tool. In addition, if a new PCM is installed, use a diagnostic scan tool to program all six of the injector codes from the original fuel injectors into the new PCM.

BALANCE TESTING

When diagnosing driveability problems which could be injector related, you need to perform an injector balance test also known as an injector kill system test, using your scan tool. With your scan tool you need to have the ability to bi-directionally control, or “kill” one injector at a time. One drawback in performing this test is there is no graph to tell you if all of the cylinders are contributing equally at the same time. To solve this problem we have to use our sense of touch, meaning we have to actually lean against the vehicle during the test and determine if we can feel any change in the RPM.

As you can see in the illustration above we are using the StarMOBILE® scan tool and the Injector Kill System Test is available. We can kill one injector at a time, lean against the vehicle and see if we can feel the RPM drop. If the RPM drop is not the same across all injectors, we then try to isolate which cylinder is not contributing the same as the others. Once we have isolated the cylinder, we can do further diagnostics to determine if we have an injector issue or a problem in some other area of the fuel system.

30 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

BALANCE TESTING

Along with the injector kill test we can perform a Cylinder Performance Test. As you can see in the illustration, the cylinder performance test begins with a value of 100%. Any drop or rise in the value indicates the PCM is compensating for either a weak or strong cylinder that is over fueling. This test is not something that is used extensively for the simple reason that it is not always very helpful.

Let’s take a step back and review our diagnostic process so far. Let’s pretend we have a vehicle in our shop that has a driveablility problem. We have done all of our preliminary diagnostics such as determining the fact we had good lift pump pressure and the set point fuel rail pressure matches the actual fuel rail pressure. At this point we have done all of our basic checks. Next we can use the cylinder performance test to determine which cylinders are either underperforming or over performing.

We can see that cylinders 3 and 6 are running at 96% and 95% respectively. We can also see that cylinders 5, 2 and 4 are running over 100% and cylinder 2 running at 105%. From this point, we could perform the injector kill test and feel which cylinders do not respond accordingly and continue our diagnostics from there.

31 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE EGR SYSTEM

The EGR (Exhaust Gas Recirculation) system is designed to reduce NOx in the exhaust system by reducing combustion temperatures. This is done by introducing inert gas (exhaust) into the combustion process. The intake air charge is diluted by a precisely metered amount of exhaust gas for the operating mode.

For example at idle and part throttle, more EGR is introduced than at high-speed cruise conditions. A cooler (2) reduces the temperature of the exhaust gas before it is combined with the intake air, which increases the ability of the existing volume of inert gas to reduce NOx. The EGR cooler is cooled by the engine coolant.

The EGR system contains the following components: • EGR Cooler (2) • EGR Valve Assembly (5) • EGR Valve Crossover Tube (4) • EGR Temperature Sensor (7) • EGR Valve Actuator (6) • EGR Air Flow Control Valve (8)

EGR is active at low load and speed ranges. Control of EGR flow is based on engine load and engine speed. The ECM (Engine Control Module) gathers information from engine input sensors, and after evaluating the input signals, uses a stored performance map to operate the EGR Valve Actuator (2) and EGR Airflow Throttle Control Valve (3). The calculation allows for a precise EGR flow rate.

The EGR Valve Assembly (1) is located at the left front of the engine, in the upper corner of the intake manifold. The EGR valve has two poppet valves connected by a valve shaft. Cooled exhaust gases flow from the EGR cooler to the center of the valve. When the valves open, exhaust gasses flow into the intake air stream from both the top and the bottom of the passage.

The EGR valve motor (actuator) (2) is a three-phase, brushless DC motor controlled by the ECM. The motor assembly also contains three Hall-effect sensors that detect EGR valve position.

We have seen EGR coolers become full of carbon and begin to malfunction. One of the reasons the EGR cooler becomes overloaded with carbon is because there have been excessive regeneration events. These regeneration events are sending fuel into the exhaust to heat the aftertreatment system up.

32 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE EGR SYSTEM

The exhaust then goes through the cooler and excessive carbon begins to build up on the walls of the EGR cooler. This can get worse. The carbon can build up within the tube going from the EGR cooler to the EGR valve. Carbon buildup on EGR systems is nothing new. We have been dealing with this issue on other applications since the beginning of the EGR system, and this application is no different.

On some 2500 and 3500 applications you may find an EGR bypass valve. The EGR Cooler Bypass Valve Assembly is mounted between the EGR crossover tube and the EGR cooler. Two mechanical cables join the units together. An electrical drive servo moves the cables to operate a butterfly plate within a cast manifold.This bypass valve closes off exhaust flow to the EGR cooler sending it straight to the EGR valve. Again, this is an option on some applications and you need to be aware that it does exist.

You will also find temperature sensors in the EGR system. One sensor is the EGR temperature sensor. The EGR temperature sensor is a negative temperature coefficient thermistor used to measure the temperature of the EGR gas flow after it exits the EGR cooler.

The Powertrain Control Module (PCM) supplies 5 volts to the EGR temperature signal circuit. To determine the temperature of the EGR gas flow, the PCM monitors the change in voltage caused by changes in the resistance of the sensor. The PCM uses the exhaust gas recirculation temperature value for the engine protection system, and also for engine emissions control.

One very important subject we need to mention is the need for an air free cooling system. You need to make sure the EGR cooler is not leaking or cracked. This would allow coolant to enter the intake. To make sure you have an air free cooling system you should use a tool that will allow you to fill the cooling system without having any air. The main reason for EGR cooler failure is air in the cooling system. Do not take any chances. We cannot stress this point enough. However you do it or whatever tool you use, make sure there is no air in the cooling system.

Another item we need to discuss is the throttle plate that can be found on the Dodge Cummins applications. This throttle plate is designed to pressure difference. As the throttle plate closes, a low pressure condition is created on the intake side while still having boost pressure. This creates a vacuum that will open the EGR valve and suck the exhaust gasses into the combustion chambers more efficiently.

When examining carbon buildup within the EGR system, we need to discuss the exhaust side of the engine. During post injection, the fuel injector is injecting fuel on the exhaust stroke. When the exhaust valve opens, the exhaust manifold will be filled with a lot of fuel. Some of this fuel can get into the EGR cooler and begin to form carbon deposits on the walls of the cooler itself. Not only will the EGR cooler begin to get clogged with carbon, but the tube from the exhaust manifold to the Exhaust Back Pressure (EBP) sensor will also become clogged with carbon. When the EBP sensor becomes fouled, it will begin to send wrong information to the ECM causing other types of driveability problems.

Lastly, the turbocharger is also at the mercy of whatever is in the exhaust system. Post injection fuel must also go through the turbocharger as well as the exhaust manifold. This will also cause carbon formation within the turbocharger itself causing the nozzle inside of the turbo to stick.

The EGR system is based on engine speed and load and is also active at low load and speed ranges. Input signals from sensors are used by the ECM to operate the EGR valve actuator and the EGR throttle control valve.

33 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE EGR SYSTEM

When viewing scan data with reference to the EGR, you will be looking at the sensor circuits. You will see EGR position sensor circuit low and high codes as well as EGR position sensor circuit performance codes. You can use the "view the EGR Commanded Position" to aid in diagnosing EGR related issues. You can view the EGR Commanded Position and the EGR Position to see if they are both the same. If they are not both the same, it is a good indication that the EGR is getting hung up on something such as carbon deposits.

The EGR airflow throttle control valve is used to increase a pressure differential between the exhaust system and the boosted intake system. The valve consists of a valve throttle plate and spring, DC motor, reduction gear drive and a potentiometer for position feedback. The valve adjusts the flow of fresh air into the engine during EGR operation. The position of the plate is based on inputs and EGR valve position.

As the plate closes, a pressure differential is created. This difference in pressure helps draw exhaust gasses into the intake stream. In turn, a blended mixture enters the intake manifold.

The throttle valve receives power from the Smart Power Relay. The ECM controls the operation of the valve based on inputs from various sensors. The DC motor in the valve assembly turns a reduction drive gear which changes the position of the valve plate. In turn, the valve closes as the ECM increases the frequency command.

Just like the EGR valve, the EGR throttle valve can and will set DTCs. These DTCs can be related to the circuit being open, high, low or the performance of the valve itself. Keep in mind this valve is spring loaded and over time the spring can become weak and cause issues with the throttle plate. It is also worth noting that you can view the EGR throttle valve parameter on a scan tool.

34 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

D1/ DH EGR BYPASS VALVE

The EGR Cooler Bypass Valve Assembly (1) is mounted between the EGR crossover tube and the EGR cooler. Two mechanical cables (3) join the units together. An electrical drive servo (4) moves the cables (3) to operate a butterfly plate (2) within a cast manifold.

Parts 1, 2, 3 and 4 are serviced as one entire assembly. Do not attempt to disassemble unit.

Since particulate filters are used on these vehicles, there is a substantial amount of heat generated during the regeneration process due to post injections. The valve shuts off the flow of exhaust gasses to the cooler in certain modes. It will in turn open a passage that allows exhaust gasses to be routed to the EGR valve and not through the cooler.

The bypass system consists of a module and an exhaust valve controlled by two cables. This module achieves communication through the CAN circuit with the ECM. CLOSED CRANKCASE VENTILATION (CCV) SYSTEM

Another emission control device you will find on the Cummins 6.7L engine, apart from the EGR and Aftertreatment systems is the Closed Crankcase Ventilation (CCV) System. Unlike the 5.9L that used a tube that was vented to the atmosphere, the CCV system is taking those gasses back into the intake system and burning them as well much like we see on gasoline engine applications.

The CCV system reroutes crankcase ventilation (blow- by) gases from the breather assembly back into the engine intake airflow to be used for combustion. The crankcase ventilation system uses a coalescing filter which captures and filters crankcase blow-by gases and then returns oil directly to the sump.

The Closed Crankcase Ventilation System (CCV) consists of several parts to make it functional. One part is the breather element (1). The breather element (1) is serviceable and prevents oil mist from entering the discharge tube of the CCV system. The breather element (1) should be replaced at 67,500 mile intervals.

Crankcase gasses travel into the breather cavity under the breather cover where they pass through a filtering media (serviceable maintenance component) which separates the oil from the crankcase gasses. The oil drains back into the engine block through two hoses (2) on the left side of the engine.

The crankcase gasses are directed through the Crankcase Depression Regulator (CDR) valve which allows the system to maintain a constant positive pressure in the crankcase. The CDR valve is a non-serviceable component located on the underside of the breather cover. Clean crankcase gasses flow from the CDR valve into the fresh air side of the turbocharger compressor.

35 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CLOSED CRANKCASE VENTILATION (CCV) SYSTEM

The CCV system contains the following components: * Cylinder Head Cover Assembly (7) * Breather Element (2) * Breather Cover (1) * Crankcase Pressure Sensor (3) * Crankcase Differential Regulator (CDR) Valve; a part of the breather filter cover (1)

The cylinder head cover assembly (7) is made of a composite material. The cover has a recessed area for the breather element and passages for oil draining from the breather element, back to the crankcase. The breather element is serviced separately. The drain tubes have one-way check valves (4), (5) and (6) that prevent oil from being forced up the tubes by excessive crankcase pressure. The external fittings to the breather tube and breather drain tube are serviceable.

The closed crankcase ventilation valve is used to vent the crankcase gases back into the intake of engine. If the crankcase ventilation filter becomes too restrictive, under high intake vacuum situations, the closed crankcase ventilation prevents the engine from siphoning crankcase gases/oil from the crankcase of the engine. The closed crankcase ventilation valve is located under the crankcase ventilation filter cover at the top of the engine.

The Crankcase Pressure (CP) Sensor is mounted on the valve cover. The CP sensor monitors crankcase pressure that builds up as the result of combustion gas blow-by. The Powertrain Control Module (PCM) uses data from the CP sensor to determine the condition of the crankcase breather (ventilation) filter. The PCM can also determine if a crankcase breather (ventilation) filter is present.

The CP sensor is a 3 wire gauge type sensor. It can measure from -10 - +10 inches of H20. The CP sensor can monitor faults such as: Crankcase pressure sensor circuit open Crankcase pressure sensor circuit high Crankcase pressure sensor circuit low

You can use your scan tool to monitor the Crankcase pressure (volts) as well as the Crankcase pressure (inches H2o).

36 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE TURBOCHARGER

The turbocharger used on the 6.7L Cummins is dramatically different than that used on the 5.9L. The 5.9L Cummins engine used a wastegate system while the 6.7L turbocharger is an electronically controlled Variable Geometry (VG) turbocharger which is a water cooled, exhaust-driven, oil lubricated compressor that increases the pressure and density of the air entering the engine. With the increase of air entering the engine, more fuel can be injected into the cylinders, which creates more power during combustion.

The VG turbocharger allows the engine to operate in a wide power and speed range to achieve the best power, torque, and engine operating conditions. The VG turbocharger can also provide engine braking and reduce engine warm up time.

The turbocharger itself is manufactured by Holset and fully serviceable with parts available from both Dodge and Holset. The main component that you will probably be servicing is the turbocharger actuator which is found on the side of the turbocharger.

The VG turbocharger assembly consists of: * Turbocharger assembly * Variable Geometry Nozzle * Water Cooled Bearing housing * Electronically Controlled Actuator

There have been numerous issues with the VGT. From experience, we have found that exhaust leaks are a huge problem when dealing with turbocharger issues. You may have squealing or high pitched sounds and you may immediately condemn the turbocharger. We are not saying the turbocharger is always at fault, what we are saying is you need to determine if you have any exhaust leaks before you condemn a good turbocharger.

37 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

THE TURBOCHARGER

You may have to remove the exhaust manifold and install new exhaust manifold gaskets. There have been cases where there were bolts missing from the exhaust manifold itself. Also make sure there are no leaks between the exhaust manifold and the turbocharger as well.

Another component you will become familiar with as you work on this engine is the VGT Exhaust Brake. The VGT Exhaust Brake works in conjunction with the engine and transmission to provide an integrated braking system to help slow the vehicle. This is commonly referred to as exhaust braking. Braking power is achieved by modulating the sliding nozzle ring to restrict the flow of exhaust gasses from the engine, this will create high back pressure on the engine. The high back pressure creates a high level of resistance to the motion of the pistons within the engine and this resistance is used to reduce engine speed and thus, the vehicle.

The exhaust brake feature will only function when the Exhaust Brake Switch is in the ON position. With the switch in the ON Position and the vehicle moving faster than 5 MPH; the exhaust brake will automatically operate when pressure is removed from the accelerator pedal allowing the ECM to see 0% throttle and 0% fuel delivery.

The charge air system consists of the charge air cooler piping, charge air cooler and intake air grid heater. The Charge Air Cooler is a heat exchanger that uses air flow from vehicle motion to dissipate heat from the intake air. As the turbocharger increases air pressure, the air temperature increases. Lowering the intake air temperature increases engine efficiency and power.

Cooler compressed air is more desirable for engine performance and emissions. Boosted air is routed to the intercooler, then into the intake. Note that system operation will be compromised if there should be any leaks caused by loose clamps, hoses, connectors or leaks in the CAC itself.

During normal engine operation we are going to see different levels of boost pressure present at different levels. If there is boost pressure present, the turbocharger will be turning at a certain speed. In the event there is a leak, the speed of the turbocharger will increase due to the fact there is a loss in boost pressure and it is working harder to keep up. One of the main reasons you find a speed sensor on the turbocharger itself is to help the ECM interpret if there is a possible boost leak.

38 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

ELECTRONICALLY CONTROLLED ACTUATOR

The Electronically Controlled Actuator is mounted to the turbocharger bearing housing. The actuator consists of an integrated controller and a gear train that controls the position of the sliding nozzle ring. The actuator uses a signal from the Engine Control Module (ECM) to control the relationship between the sliding nozzle ring and turbine blades.

Moving the nozzle ring rearward or forward redirects the exhaust flow so that the turbine wheel spins faster or slower as needed

* If the sliding nozzle is moved rearward, the turbocharger builds more pressure (turbine wheel moves faster) * If the sliding nozzle is moved forward, the turbocharger builds less pressure (turbine wheel moves slower)

Pictured above is the actuator both mounted to the turbocharger and removed from the turbocharger. When removed, you can see the actuator has a small gear and also a large chamber. This large chamber is actually for coolant passage. For those of you not familiar with this type of turbocharger, it is cooled by engine coolant. As we noted earlier, this turbocharger gets very hot, therefore it is necessary to cool the actuator with coolant.

Pictured above is the sector gear that is moved side to side by the actuator gear. This sector gear controls the sliding nozzle in and out of the slots.

39 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

TURBOCHARGER HANDS ON AND RECAP

The 6.7L VGT for either the Cummins or Dodge applications is identical other than a slight difference in mounting height. The actuator is mounted to the side of the turbocharger and is controlled via CAN by the ECM. This means the ECM has full communication and control over the actuator, not to mention any issues with actuator performance will be reported to the ECM via the CAN and the appropriate DTCs will be set.

Also we will have a turbocharger speed sensor. This speed sensor is used by the ECM to determine if there is possibly a boost leak. On the scan tool this parameter will be displayed in kRPM which stands for thousands of revolutions per minute.

On the Dodge 6.7L application you will have the ability to drill, tap and install the appropriate de-carbonizing agent which makes the VGT fully serviceable for the purpose of removing carbon. This is important because numerous regeneration events may cause carbon buildup within the turbocharger.

We cannot stress enough the practice of vacu-filling the cooling system. You need to make sure the EGR cooler is not leaking or cracked. This would allow coolant to enter the intake. To make sure you have an air free cooling system you should use a tool that will allow you to fill the cooling system without having any air. The main reason for EGR cooler failure is air in the cooling system. Do not take any chances. We cannot stress this point enough. However you do it or whatever tool you use, make sure there is no air in the cooling system.

Lastly, do not miss-diagnose or condemn a turbocharger because of exhaust leaks. From experience, we have found that exhaust leaks are a huge problem when dealing with turbocharger issues. You may have squealing or high pitched sounds and you may immediately condemn the turbocharger. We are not saying the turbocharger is always at fault, what we are saying is you need to determine if you have any exhaust leaks before you condemn a good turbocharger.

TURBOCHARGER EXHAUST BRAKE FUNCTION

The VGT works in conjunction with the engine and the transmission to provide an integrated braking system used to help slow the vehicle. This is commonly called exhaust braking. This braking power is achieved by modulating the turbo sliding nozzle ring to restrict the flow of exhaust gases from the engine, which in turn creates a high back pressure on the engine. The high back pressure creates a high level of resistance to the motion of the pistons within the engine and this resistance is used to reduce engine speed and thus vehicle speed.

The exhaust brake feature will only function when the driver turns the exhaust brake switch to the on position. Once the switch is in the on position and the vehicle is moving faster than 8 k/h (5 MPH); the exhaust brake will automatically operate when the driver removes pressure from the throttle pedal allowing the engine to see 0% throttle and 0 fuel delivery.

Exhaust braking is most effective when the engine RPM is higher. The automatic transmission has been programmed to downshift more aggressively when the exhaust brake is enabled to increase brake performance. Use of automatic transmission Tow/Haul Mode improves interaction between the engine and transmission.

40 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

TURBOCHARGER EXHAUST BRAKE FUNCTION

Inputs to the exhaust brake feature include: * Coolant temperature * Ambient air temperature * Exhaust manifold pressure sensor * Throttle pedal position sensor

Fault codes with any of these sensors will cause the exhaust brake feature to be disabled.

The exhaust brake feature can also be used to reduce the engine warm up time. To use the exhaust brake as a warm-up device, the vehicle must be moving less than 8 k/h (5 MPH), the exhaust brake switch must be in the on position, and the coolant temperature must below 82°C (180° F) and ambient temperature below 15.5°C (60° F).

TURBOCHARGER COOL DOWN

The most common turbocharger failure is bearing failure related to repeated hot shutdowns with inadequate “cool-down” periods. A sudden engine shut down after prolonged operation will result in the transfer of heat from the turbine section of the turbocharger to the bearing housing. This causes the oil to overheat and break down, which causes bearing and shaft damage the next time the vehicle is started.

Letting the engine idle after extended operation allows the turbine housing to cool to normal operating temperature. The following chart should be used as a guide in determining the amount of engine idle time required to sufficiently cool down the turbocharger before shut down, depending upon the type of driving and the amount of cargo.

41 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

VGT POWER INPUT

The VGT actuator receives power from the Smart Power Relay. The communication between the ECM and the actuator takes place using a J1939 data link. SAE J1939 has been adopted widely by diesel engine manufacturers. One driving force behind this is the increasing adoption of the engine Electronic Control Unit (ECU), which provides one method of controlling exhaust gas emissions within the US. Consequently, SAE J1939 can now be found in a range of diesel-powered applications: vehicles (on- and off-road), marine propulsion, power generation and industrial pumping.

The actuator will perform its own self diagnostics and will send any failures detected back to the ECM using this data link. These failures can include: * Turbocharger Boost Control Module Supply Voltage Circuit Low * Turbocharger Boost Control Module Supply Voltage Circuit High * Turbocharger Boost Control Circuit Performance * Turbocharger Boost Control Circuit Position Exceeded * Turbocharger Boost Control Module Performance

By using a scan tool such as the StarMOBILE® and the WiTECH®, you will be able to view information regarding the turbocharger such as: * Turbo Frequency Input (HZ) * Desired VGT Position (%) * VGT Position (%)

A great way to view these parameters in a real world setting is during a road test. This will tell you how the turbocharger is functioning under any given engine load or driving condition.

ACTUATOR COOLANT PASSAGE

As we reinforce the information we covered earlier regarding the VGT actuator, it is important to remember the VGT actuator on the Cummins 6.7L is water cooled. It can also be serviced separately from the VGT. After installing a new actuator a locating procedure must be performed. Also, there is an install Command and Learn Command to further ensure proper positioning of the actuator. Make sure you follow the OE removal and installation procedures when servicing the VGT actuator.

The Cummins 6.7L VGT is also equipped with a speed sensor, (pictured left), that is located on the top of the bearing section of the VGT assembly and can be serviced separately. The speed sensor is a variable reluctance sensor which, along with the VGT shaft, generates an AC signal. This signal is used by the ECM to interpret how fast the turbocharger is spinning and to calculate estimated boost pressure.

42 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

ACTUATOR COOLANT PASSAGE

In taking a closer look where the speed sensor connects to the VGT, we notice there is only one bolt holding the speed sensor in place. When replacing the speed sensor, make sure the passage is free from any debris that may cause damage or installation problems. Any debris can and will cause communication issues between the sensor and ECM.

Just like any other sensor, the turbo speed sensor is monitored by the ECM and will report faults. These faults can include: * Turbo Speed Sensor Circuit Malfunction * Turbocharger Speed Data Valid But Below Normal Operational Range * Turbocharger Speed Sensor Circuit Performance * Turbocharger Turbine Overspeed

Tech Tip: As silly as this may sound, we all need to keep in mind and remember what a Diagnostic Trouble Code (DTC) really is. A DTC is an indicator that a test performed by a controller or module, in this case the ECM, and the test has failed. Let the DTCs aid you in figuring out what the problem is!

Viewing scan tool data can aid you greatly in determining faults with the VGT and its related components. Using the appropriate scan tool you can view the following parameters: * Turbo Speed (KRPM) * Estimated Turbo Speed (KRPM)

Keep it as simple as possible. You may want to start by road testing the vehicle and monitoring the Turbo Speed parameter and see if you are getting any boost. After you have leak tested the system and found no faults, then you can use the scan tool data to help you determine what the cause of the fault is.

43 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

LAUNCH DRB III

When diagnosing problems and issues with the Cummins 5.9L and Cummins 6.7L, a good scan tool is critical. The scan tool that is recommended by Dodge and used in the dealerships is the wiTECH®. The other scan tool software that can be used as well is the StarMOBILE®.

Pictured above is a screen capture of the wiTECH® during the vehicle connection phase. As you can see we are connected to a 2011 RAM 2500 with a 6.7L. As we discussed earlier, one of the advantages to using the wiTECH® is that the software has the DRB III® emulator built into it. At the bottom right hand corner of the screen, you can see the “Launch DRB III” button.

For those of you who are not familiar with using the DRB III® scan tool, the Cummins 5.9L 2002 and earlier required the use of the DRB III®. Also, the common rail injection systems between 2003 and 2005 required the use of the DRB III® as well. An easy way to remember this is that anything before 2005 required the use of the DRB III® scan tool.

With the wiTECH® you do not need to use the DRB III®. All you need to do is click on the Launch DRB III® button and the DRB III® emulator will launch.

This will make your life a whole lot easier. Think about it, you now have two scan tools in one. One scan tool for the old applications and one scan tool for the new applications.

44 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

Once you have connected to vehicle, the wiTECH® will display the vehicle view screen. The vehicle view screen will consist of the Vehicle Topography, Common Vehicle Tasks and Vehicle ID. The vehicle typography section will display all of the modules that communicate over the network. If any of the modules on the network have a re-flash available, a green circle with a white lightning bolt will appear over the module name.

To the left of the vehicle topography is a legend that will help you indicate which modules are available on the vehicle, which modules have re-flashes available and which modules have DTCs.

At the bottom of the screen is the Common Vehicle Tasks window. This area lets you view all DTCs, run diagnostic procedures, view customer preferences, prepare the vehicle for re-flashing as well as viewing freeze frame data and clearing DTCs.

Looking closer at the vehicle topography you can see an image representing the data link connector (DLC). You can also see when you connect to the DLC, you are immediately communicating with the TIPM module. As we discussed earlier, the TIPM module is the gateway to communicating with all of the other modules on the network.To select which module you want to view, simply click on the module name in the vehicle topography.

45 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

Looking at the DTCs at the bottom of the screen, you can see either the DTC is active or stored. Knowing the condition on how the DTC is displayed is very important. If the DTC is shown as active, it means the test being run continues to fail. Stored DTCs are not necessarily active but stored in the memory of the module. One thing you would want to do with a stored code is view the freeze frame data and attempt to recreate the fault conditions and see if the code becomes active. If the DTC becomes active it means you have a hard fault and you need to follow the diagnostic process for the DTC.

By clicking on the PCM, the scan tool will tell you everything there is available about the module. At the top of the menu bar there is a set of tabs you can click on to tell you certain things about the module as well as tests you can perform. The tabs consist of the following: * Flash * Data * DTCs * Actuators * System Tests * Misc. Functions * ECU Details

When we focus first on the flash option we can see there is a flash update available for the PCM. If we click on the available flash we are able to view service information and TSBs related to this particular flash revision.

On the next few pages you will see a sample TSB regarding re-flash of the PCM. TSB is courtesy of Chrysler Corporation.

46 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

47 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

48 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

49 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL

As you read the TSB, you should be able to obviously see why re-flashing is so important. Automobile manufacturers are constantly making changes to their controller software – making cars and trucks more efficient, fixing problems that have been discovered, fine tuning components and systems, updating cut points as cars and trucks age, solving problems such as rough idle and hard starting, repairing emissions related problems and many others.

Also, it is important to realize new controllers replaced in a vehicle require programming to match the exact specifications and option list on the car being repaired.

Many of the TSBs issued by automobile manufacturers require reprogramming with the latest software updates to repair problems that are occurring with vehicles on the road even after their warranties have expired.

Always look to the TSBs for either a symptom or condition you have BEFORE beginning any of the OEM diagnostic pinpoint tests. It could be very likely the engineers at Chrysler have seen this problem and have an updated calibration for a module to solve the problem. Re-flash the module, clear the codes, road test the vehicle. If the DTC or symptom comes back, then you can move on to the OEM pinpoint test.

Keep in mind that in the event you do have to flash a new module or re-flash an existing module, you will need a SKIM code reader. The wiTECH® will not read the SKIM code. If you have a good relationship with the local dealership, you could give someone in the service department the VIN of the vehicle you are working on and they will be able to get you the SKIM code.

Clicking on the ECU Details tab will give you all of the information available for the ECU. An important item you need to pay attention to is the VIN. There have been times when trucks have come into the shop with a driveability problem and when scanned, the VIN of the ECU does not match the VIN of the vehicle. Someone had tried to use a replacement ECU from another vehicle and the calibration of the new ECU was not able to run the vehicle as it was designed to do.

50 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH SCAN TOOL (MISCELLANEOUS FUNCTIONS)

Located in the miscellaneous functions tab there is a function called “Reset ECU”. This function will reset the ECU to the original basic factory programming. The ECU is a module that will learn what we call “Bad Habits”. These bad habits come from the learn procedures the ECU performs while the vehicle is in operation.

After a period of time, it could be the vehicle doesn’t run right. This could be due to harsh shift points with the transmission or it could be the ECU has learned bad fuel strategies. When these things happen, it is sometimes a good idea to reset the ECU to the original factory programming and let it start the learning process all over again.

INJECTOR QUANTITY ADJUSTMENTS (IQA)

As we discussed earlier, the Cummins 6.7L engine uses injectors that are IQA coded. Each fuel injector has a six- digit alphanumeric correction code. The correction code is printed on the intake side of the fuel injector and is used to identify injector calibration. When replacing any fuel injectors, this code must be entered into the vehicles Powertrain Control Module (PCM) using a diagnostic scan tool. In addition, if a new PCM is installed, use a diagnostic scan tool to program all six of the injector codes from the original fuel injectors into the new PCM.

Within the miscellaneous functions, you will see the option “Injector Quantity Adjustment”. After installing a new injector, this is where you go to program it to the vehicle you are working on. Anytime you replace an injector you need to make sure to note which cylinder number you installed it on and the number on the injector.

51 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

INJECTOR QUANTITY ADJUSTMENTS (IQA)

For those of you who are not familiar with the injectors on the 6.7L it is important to remember that very rarely will two injectors share the same IQA code. If you have a vehicle with driveability problem and you have narrowed it down to the injectors, you should verify that the IQA code on the injectors match the IQA the scan tool is asking for.

STATIONARY DESOOT

The Stationary Desoot menu option will allow you to run a manual regeneration. The regeneration process is a big challenge when working on these trucks because they usually require a code to be set or a message to be displayed on the CCN before a manual regeneration can be performed.

If you have a DTC or a message displayed on the CCN, it is possible to just drive the truck real hard and get the temperature of the DPF hot enough to burn off all of the particulate without connecting a scan tool. However, you may have a customer saying they are running a regeneration event every day or every other day which is way too frequent. So what do you do? You need to use the scan tool to run a manual regeneration.

The key aspect of running a manual regeneration event is safety. The heat generated in the exhaust system can and will exceed 1,000° F. Running a regeneration inside of your shop with these types of temperatures can be dangerous. Run the regeneration outside in the open, away from other vehicles and also away from any combustible materials.

TIPM MODULE

Pictured above is a screen capture from the wiTECH® scan tool with the data available for the TIPM module. As you can see the tabs available for the TIPM module are the same as those that were available for the ECU.

As we discussed earlier, the TIPM module is responsible for body related functions such as the horn, lighting, turn signals etc. One of the other responsibilities of the TIPM module is to be the gateway of communication from the scan tool to the entire vehicle.

52 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

TIPM MODULE

Within the Actuators tab there is a very large list of actuators you have bi-directional control over. If you have a DTC related issue to any of these systems, you can bi-directionally control the actuator and test the circuit to determine if they are working correctly.

As with the ECU, the Misc. Functions tab is where you will be able to re-program the TIPM module. This is where you are able to program door lock functions, program illumination entry times, program tire size etc. This is a nice feature if you have a customer that would like to program the car to their liking, or if they do not like the factory settings for something like how long the interior lamps stay on after the ignition key is removed. It could be they want the lamps to stay illuminated longer or shorter.

One thing to keep in mind is if you replace the TIPM module, you will need to restore the vehicle configuration to the basic factory settings. To do this you will need to know the VIN of the vehicle and if the customer has certain settings they like, you need to make a note of them as they will have to be reprogrammed as well.

53 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH WCM

Another important module we need to discuss is the WCM module. This is where you will enter the SKIM code of the vehicle you are working on when either flashing or re-flashing modules.

After clicking on the WCM module on the main menu screen, again, you will have the same option tabs available as you had with the ECU and the TIPM modules. If we click on the Misc. Function tab, you will see the second item on the list is PCM Replaced.

When you click on the PCM Replaced option a warning screen will appear warning you of the loss of key information which will require the cutting and programming of new keys. This may make you a bit nervous but don’t worry. If you are replacing a PCM and you need to enter the SKIM code, you are in the correct place.

54 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH WCM

Once you click on the Continue button, you will be prompted to enter the SKIM code of your vehicle.

NOTES

55 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DTC

One major advantage of the wiTECH® is how the tool interfaces with the OEM website. This can be easily demonstrated with a DTC stored in memory. At the main menu you can see our subject vehicle has a P013A – O2 Sensor 1/2 Slow Response – Rich to Lean. By clicking on the DTC, then clicking on the green “Play” arrow to the right, a new window will open displaying the information for that particular DTC. Reading, understanding and following these OEM pinpoint tests are some of the most important things to do when trying to diagnose a DTC based fault. We cannot stress this enough. These charts and wiring diagrams are the best way to determine a fault and verify the repair after it is complete.

This means you will be able to see the entire pinpoint procedure with wiring diagrams as shown below. Pinpoint procedure and wiring diagram courtesy Chrysler Corporation.

P013A-O2 SENSOR 1/2 SLOW RESPONSE - RICH TO LEAN Special Tools: Click to display a list of tools used in this procedure

56 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DTC

57 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DTC

58 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DTC

Were anv Exhaust System leaks found?

Yes • Perform the appropriate repairs to the Exhaust System. • Perform the POWERTRAIN VERIFICATION TEST- 6.7L. (Refer to 28- DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No • Go To 5

5 .CHECK FOR AN EGR LEAK

1. Look for visible signs (soot streaks) of an external EGR leak.

Were any EGR leaks found?

Yes • Perform the appropriate repairs to the EGR system. • Perform the POWERTRAIN VERIFICATION TEST- 6.7L. (Refer to 28- DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

No • Go To 6

6 .CHECK THE 0 2 SENSOR

Excessive soot build Ul> can be caused by over fueling. If excessive soot build Ul> is 11resent, the fuel syste111 operation should be checked and both of the 0 2 sensors should be cleaned.

1. Remove the 02 Sensors.

2. Clean the soot from the 02 Sensors.

3. Reinstall the 02 Sensors.

4. Turn the ignition on.

5. With the scan tool, erase DTCs.

6. Turn the ignition off for 75 seconds.

7. Start the engine and let idle up to five minutes.

18. 1With the scan tool, read DTCs.

59 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DTC

60 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH UTILITIES AND REPORTS

Located at the top left of the screen you will find the Utilities and Reports functions of the wiTECH®. When clicking on the Utilities function our first option is TechCONNECT. The TechCONNECT function will immediately take us to either to the Tech Authority website or to the Dealer Connect website depending on what subscription you have.

Once at either of the OEM websites we will have the entire service manual available for the vehicle you are working on.

61 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH UTILITIES AND REPORTS

You should also notice the VIN, Year, Model and Engine have all been identified by the software. This ensures you are looking at the right information for the vehicle in your shop.

At the top of the screen you have several tabs available. They include the following: * Service Bulletins/Recalls * Service Info * Wiring * Owner’s Manuals * Parts * Diagnostics * Collision Info

After clicking on the Service Bulletins/Recalls tab, a list of numbered topics will appear in the left side bar of the screen. When we click on 09 – Engine, we can see there are roughly 8 TSBs and recalls that apply to this vehicle with this VIN. Clicking on each of the other tabs will give you access to all of the information available for the vehicle you are working on.

62 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH UTILITIES AND REPORTS

The reports tab will allow you to print reports for the following items: * Configuration Report * ECU Details Report * Event Data Report * Freeze Frame Report * Loss of Communication Report * Vehicle Scan Report

Pictured above is a screen capture of the Vehicle Scan Report for our subject vehicle. This report will give you the ECU, Name, Original VIN, Current VIN, Part Number, Flash Part Number, H/W Version, S/W version and the Variant. This is a nice report to view if you want to fully review the information for all of the modules on the vehicle. This will show you if the VINs of the module match, the part number of the module if you need to order one and also the flash number of the module that is installed.

63 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

STARMOBILE SCAN TOOL

As we briefly discussed the use of the wiTECH® scan tool we also need to discuss the use of the StarMOBILE® scan tool software. Please understand, whichever scan tool software you use, you can still use the StarMOBILE® communication interface module for both.

The StarMOBILE® communication interface module can act as a miniature scan tool as it will read DTCs, clear DTCs and it will also give you the ability to read limited data. This device is limited in its diagnostic functions and should not be interpreted to take the place of either the wiTECH® or StarMOBILE®.

Once StarMOBLE® has achieved communication with the vehicle it will run a scan and bring you to the main menu screen pictured above. As you can see, while the appearance of the screen is different from the wiTECH®, the menu options are similar. However, StarMOBILE® does have its limitations. It will only communicate with the older model vehicles. Newer vehicles will require the wiTECH® software. Listed on the next pages are the vehicles that will use StarMOBILE® or DRB III software.

64 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

STARMOBILE SCAN TOOL

65 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

STARMOBILE SCAN TOOL

66 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

STARMOBILE SCAN TOOL

67 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

WITECH DIAGNOSTICS - MASS AIR FLOW

The Mass Airflow (MAF) sensor is a frequency based device located on the air cleaner cover. A constant voltage is applied to a heated wire on the sensor. This wire is positioned in the air cleaner air stream and is heated by the electrical current that the voltage produces. As air flows across it, it cools down. The heated wire or film is a positive temperature coefficient resistor. This means that its resistance drops when its temperature drops. The drop in resistance allows more current to flow through it in order to maintain the programmed temperature. This current is changed to a frequency which is sent to the Powertrain Control Module (PCM) and interpreted as air flow. Adjustments for air temperature and humidity are taken into consideration because they also affect the temperature of the heated wire or film.

The MAF sensor plays a critical role in regards to EGR monitoring. In this case, when the EGR is open, there should be a sudden change in mass air flow due to the fact the exhaust gases are taking up space, therefore reducing the amount of air flow.

With regards to the EGR, if you ever have EGR DTCs, it is a good idea to make sure you don’t have carbon buildup between the cooler and the EGR, but also you may want to run a regeneration event. If there is excessive backpressure in the exhaust, this can and will cause EGR DTCs to be generated.

Next to the MAF sensor is the Air Intake Pressure Sensor. For the most part, you will not see these vehicles equipped with a filter minder, which is used to alert you, when to replace the air filter. In these applications an Air Intake Pressure Sensor is used.

68 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

RESETTING THE OIL CHANGE LIGHT WITHOUT A SCAN TOOL

The change oil indicator gives an indication to the vehicle operator when a duty-cycle algorithm contained within the software of the Powertrain Control Module (PCM) determines that a recommended oil change interval has been attained. This indicator is controlled by the instrument cluster logic circuit based upon cluster programming and electronic messages received over the Controller Area Network (CAN) data bus from the PCM.

The change oil indicator function of the odometer display unit is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the odometer VFD change oil indication will always be OFF when the ignition switch is in any position except ON or START. The instrument cluster will turn ON the change oil indicator for the following reasons:

Change Oil Indicator Lamp-On Message - Each time the ignition switch is turned to the ON position and the cluster receives an electronic change oil indicator lamp-ON message from the PCM indicating that a duty-cycle based recommended oil change interval has been attained, the change oil indicator will be illuminated for about three seconds, until the trip odometer reset switch button is depressed, or until the ignition switch is turned to the OFF position, whichever occurs first.

Change Oil Indicator Reset Procedure - Once an engine oil change has been completed, the PCM duty cycle counters can be reset using the following procedure. Turn the ignition switch to the ON position, but DO NOT start the engine. Slowly depress and release the accelerator pedal fully three times within ten seconds. Turn the ignition switch to the OFF position. If the change oil indicator illuminates the next time the engine is started, repeat this procedure.

The PCM continually monitors numerous sensor inputs to determine the duty-cycles to which the engine is being subjected. A pre-programmed algorithm within the PCM then determines when to send the proper lamp-ON or lamp-OFF message to the instrument cluster, also known as the Cab Compartment Node (CCN).

69 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

RESETTING THE DRIVER INFORMATION CENTER WITHOUT A SCAN TOOL

PERFORM SERVICE INDICATOR - RESET

The “Perform Service” message will display on the Electronic Vehicle Information Center each time you turn the ignition switch to the ON/RUN position to indicate a emission maintenance is required. To reset the “Perform Service” indicator system (after performing the scheduled maintenance) refer to the following procedure:

1. Turn the ignition switch to the ON position (Do not start engine). 2. Press and release the brake pedal two times. 3. Fully depress the accelerator pedal slowly two times within 10 seconds. 4. Turn the ignition switch to the OFF/LOCK position.

NOTE: If the indicator message illuminates when you start the vehicle, the “Perform Service” indicator did not reset. If necessary repeat this procedure.

CUMMINS 5.9L STARMOBILE

When dealing with the Cummins 5.9L engine, it is important to note the fact it has issues with the common rail injection system just like the 6.7L. However, unlike the 6.7L, the 5.9L has very limited bi-directional control, but you will be able to perform the cylinder performance test, the injector kill test as well as resetting the ECU and other learned memory counters.

Once we have connected the scan tool to the vehicle we can see the software has identified our truck as a 2006 DR with a 5.9L Diesel. Also note the software has identified the VIN of our vehicle.

70 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L STARMOBILE

After clicking on the ECU View option, all of the available electronic control units equipped on the vehicle are available for view. Listed first is the PCM followed by the ABS module and so on. To the right of each controller you have the ability to observe if the controller is active, if it has DTCs and what BUS the controller is communicating on.

NOTES

71 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L STARMOBILE

After clicking on the PCM, a screen appears giving us the PCM overview. The PCM overview will provide you with the hardware and software versions, the part number and country code. Below the basic information are buttons that will allow you to view the data display, actuators, access misc. functions, view DTCs and more options.

One thing to remember is the StarMOBILE® software will only work on 2011 and earlier trucks. If you are working on 2011 ½ or later trucks, you will need to use the wiTECH® software.

After clicking on the Data Display icon we have the ability to view various parameters as we did earlier using the wiTECH®. Included in these parameters are the fuel pressure setpoint and the fuel pressure sensor. As we discussed earlier, these two parameters are critical when diagnosing common rail fuel injection driveability problems.

72 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L STARMOBILE

Backing out to the previous menu we have chosen the Actuators icon. Notice there are not as many actuators that you will have bi-directional control over but the ones that are listed can be very useful such as the Lift Pump Relay. Turning the lift pump relay on and off is a great way to test the lift pump pressure to determine if the lift pump or its circuits are faulty.

Just like the wiTECH®, the Misc. Functions will give you the ability to reset the applicable ECUs back to their factory default settings. You can also check the PCM VIN to make sure the vehicle is using the correct PCM and is coded to the VIN.

73 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L STARMOBILE

Under the More Options icon you will have the ability to run special system tests such as the Injector Kill Test and the Cylinder Performance Test.

CUMMINS 5.9L CYLINDER TEST

The cylinder performance test will provide you with data that in turn will help you determine the contribution between cylinders. While this test is useful and running it has its advantages, it is not always helpful. However, this test will give you a general idea if all of the cylinders are contributing equally.

One thing we need to point out in regards to running this test on the Cummins 5.9L and 6.7L engines. The 5.9L and 6.7 use an overhead valve train that can and will require valve adjustments. Valve adjustments play a huge part in the performance of these engines.

74 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L INJECTOR KILL TEST

When diagnosing driveability problems which could be injector related, you need to perform an injector balance test, also known as an injector kill system test, using your scan tool. With your scan tool you need to have the ability to bi-directionally control, or “kill” one injector at a time. One drawback in performing this test is there is no graph to tell you if all of the cylinders are contributing equally at the same time. To solve this problem we have to use our sense of touch, meaning we have to actually lean against the vehicle during the test and determine if we can feel any change in the RPM.

As you can see in the illustration above we are using the StarMOBILE® scan tool and the Injector Kill System Test is available. We can kill one injector at a time, lean against the vehicle and see if we can fell the RPM drop. If the RPM drop is not the same across all injectors, we then try to isolate which cylinder is not contributing the same as the others. Once we have isolated which cylinder is not contributing, we can do further diagnostics to determine if we have an injector issue or a problem in some other area of the fuel system.

NOTES

75 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L PRESSURE OVERRIDE TEST

One of the tests Dodge does recommend you perform on the 5.9L is the Fuel Pressure Override Test. This can be confusing because when you look this test up on the OEM website it is called the Injector Return Flow Test. What we want to make clear is we are just measuring the total return for all six injectors.

Below is a copy of the Injector Return Flow Test Courtesy Chrysler Corporation.

76 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L PRESSURE OVERRIDE TEST

As we activate the test using the scan tool, you can see that before the test starts our engine rpm is approximately 750 rpm, the fuel pressure is a approximately 6,780 psi and the fuel pressure voltage is approximately 1.54 volts.

77 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L PRESSURE OVERRIDE TEST

As the test begins, the engine rpm increases, the fuel pressure increases and the fuel pressure voltage also increases. This is the point in the test that we would begin collecting fuel from the injectors in a graduated cylinder. As specified in the test, we want to see less than 160 milliliters within a 30 second time period.

Excessive return could mean extensive wear to the ball and seat within the injector. This is something to consider when buying rebuilt or remanufactured injectors. You have no way of knowing the condition of the ball and seat on an injector that was rebuilt by a non Bosch® approved remanufacturer.

78 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L HIGH PRESSURE FUEL PUMP

A Robert Bosch high-pressure fuel injection pump is used. The pump is attached to the back of the timing gear housing at the left /front side of the engine.

The fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure is then accumulated in the fuel rail. High pressure fuel is constantly supplied to the injectors by the fuel rail. The Engine Control Module (ECM) controls the fueling and timing of the engine by actuating the injectors.

Fuel enters the system from the electric fuel transfer (lift) pump, which is located in the fuel tank. Fuel is forced through the fuel filter element and then enters the Fuel Pump/Gear Pump, which is attached to the rear of the fuel injection pump. The Fuel Pump/Gear Pump is a low-pressure pump and produce pressures ranging from 551.5 kpa (80 psi) to 1241 kpa (180) psi. Fuel then enters the fuel injection pump. Low pressure fuel is then supplied to the FCA (Fuel Control Actuator).

The FCA is an electronically controlled solenoid valve. The ECM controls the amount of fuel that enters the high- pressure pumping chambers by opening and closing the FCA based on a demanded fuel pressure. The FPS (Fuel Pressure Sensor) on the fuel rail provides the actual fuel pressure. When the actuator is opened, the maximum amount of fuel is being supplied to the fuel injection pump. Any fuel that does not enter the injection pump is directed to the cascade overflow valve. The cascade overflow valve regulates how much excess fuel is used for lubrication of the pump and how much is returned to the tank through the drain manifold.

Fuel entering the injection pump is pressurized to between 300-1600 bar (4351-23206 psi) by three radial pumping chambers. The pressurized fuel is then supplied to the fuel rail.

79 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L CASCADE OVERFLOW VALVE

The cascade overflow valve maintains the crankcase pressure inside of the injection pump and is located on top of the high pressure injection pump. This valve can be removed from the pump without removing the pump from the truck. This means you have the ability to connect a hose to the valve hole, crank the engine and collect fuel from the injection pump.

By performing this test, you will be able to determine if the fuel in the system is either contaminated of just plain bad. If the fuel is in bad condition or contaminated, you can bet that the fuel in the rail is contaminated as well. This type of bad fuel condition can and will lead to injector failure. If you are replacing injectors, you had better make sure the fuel in the system is good or you could possibly compromise a new injector.

CUMMINS 5.9L FCA

The FCA is an electronically controlled solenoid valve. The ECM controls the amount of fuel that enters the high- pressure pumping chambers by opening and closing the FCA based on a demanded fuel pressure. The FPS (Fuel Pressure Sensor) on the fuel rail provides the actual fuel pressure. When the actuator is opened, the maximum amount of fuel is being supplied to the fuel injection pump. Any fuel that does not enter the injection pump is directed to the cascade overflow valve. The cascade overflow valve regulates how much excess fuel is used for lubrication of the pump and how much is returned to the tank through the drain manifold.

80 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

CUMMINS 5.9L FCA

If you were to disconnect the FCA while the engine is running, fuel rail pressure would go over 22,000 psi. This is not a practice you should even consider. You may want to disconnect it for cranking tests, but you do not want to disconnect it while the engine is running.

One component we haven’t discussed yet is the pressure relief valve. If you disconnect the FCA with the engine running, the pressure relief valve may open and relieve the excess pressure which is not a good thing. The pressure relief valve is not designed to be cycled on and off extensively. Once the pressure relief valve is popped open, it will likely stay open and no pressure will build within the fuel rail.

There is scan data available for viewing with regards to the FCA. The values for the FCA are: * Fuel Pressure Regulated Output (%) * Fuel Pump Current (mA) i.e. FCA amperage draw

NOTES

81 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMMON RAIL EXPLAINED

The fuel system used on the Cummins engine is an electronically controlled, Bosch HPCR (High-Pressure Common Rail) system. The HPCR system consists of five main components:

1- Electric Fuel Transfer (lift) Pump Located in the Fuel Tank 2- Fuel Pump/Gear Pump (attached to fuel injection pump) 3- High-Pressure Fuel Injection Pump 4- Fuel Injection Rail 5- Fuel Injectors Also to be considered as part of the overall fuel system are: * Accelerator Pedal * Air Cleaner Housing/Element * Check Valve Banjo Fitting at Rear of Cylinder Head * Fuel Connector Tubes * Fuel Drain Manifold (passage) * Fuel Drain Valve (at filter) * Fuel Filter/Water Separator * Fuel Heater * Fuel Heater Relay * Fuel Transfer Pump Relay * Fuel Level (gauge) Sending Unit * Fuel Pressure Limiting Valve * Fuel Tank * Fuel Tank Module (containing a fuel gauge sending unit, separate fuel filter located at bottom of tank module, and fuel transfer pump) * Fuel Tank Filler/Vent Tube Assembly * Fuel Tank Filler Tube Cap * Fuel Tubes/Lines/Hoses * High-Pressure Fuel Injector Lines

82 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMMON RAIL EXPLAINED

* In-Tank Fuel Filter (at bottom of fuel tank module) * Low-Pressure Fuel Supply Lines * Low-Pressure Fuel Return Lines * Overflow Valve * Quick-Connect Fuel Line Fittings * Accelerator Pedal Position Sensor (APPS) Located in Cab * Water Draining (maintenance) * Water-In-Fuel (WIF) Sensor * Screened Banjo Bolt

The fuel injection pump supplies high pressure to the fuel rail independent of engine speed. This high pressure fuel is then accumulated in the fuel rail. High pressure fuel is constantly supplied to the injectors by the fuel rail. The Engine Control Module (ECM) controls the fueling and timing of the engine by actuating the injectors.

Fuel entering the injection pump is pressurized to between 200-1800 bar (2900-26107 psi) by three radial pumping chambers. The pressurized fuel is then supplied to the fuel rail

Pictured above is a fuel rail from a Cummins 5.9L engine. Mounted on the fuel rail are the Fuel Rail Pressure (FRP) sensor and the fuel pressure relief valve. The fuel pressure sensor monitors actual high-pressure within the fuel rail. An output signal from this sensor (relating to fuel pressure) is sent to the Powertrain Control Module (PCM).

83 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

COMMON RAIL EXPLAINED

For the most part, the FRP sensor has been a very reliable component of the common rail injection system. When we have seen a breakdown of the fuel pressure within the rail, fuel leaks have been the main culprit.

The fuel pressure relief valve will pop open at a pre-determined pressure which is normally above 26,000 psi. The fuel pressure relief valve is plumbed to the fuel return system and If the injection system over pressurizes, the pressure relief valve will pop open to relieve the excess pressure. The excess fuel is then returned to the fuel tank.

COMMON RAIL EXPLAINED

Pictured above is a diagram of the common rail injection system for a Cummins 6.7L engine. Unlike the 5.9L engine, the fuel pressure relief valve is located at the end of the fuel rail (10). The basic concept of how this valve works is still the same except for the fact return fuel is pumped back into the system via a banjo fitting located to the right of the valve itself.

Another difference is the FRP sensor is located at the opposite end of the fuel rail and not on top like the 5.9L engine. Do not confuse this sensor with the pressure control solenoid. This is a sensor, not a solenoid.

84 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL RAIL PRESSURE SENSOR

As we discussed earlier, the fuel pressure sensor is mounted vertically near the top/center of the fuel rail on the Cummins 5.9L engine and in the fuel rail at the rear on a Cummins 6.7L engine. The fuel pressure sensor monitors actual high-pressure within the fuel rail. The FRP sensor is a 5 volt referenced sensor and provides a variable voltage signal to the ECM to report the actual fuel rail pressure. The voltage can vary between 0.5 to 4.5 volts.

If the FRP sensor fails, the ECM will substitute a default pressure value. If you ever see the fuel rail pressure set point and the actual fuel rail pressure exactly the same on your scan tool, this probably indicates the FRP sensor has failed and the ECM is using a default value. If this type of failure does occur, you will have a DTC set as well.

The FRP sensor is monitored by the ECM and can set the following faults: * Fuel Rail Pressure Sensor High * Fuel Rail Pressure Sensor Low * Fuel Rail Pressure Too High * Fuel Rail Pressure Too Low * Fuel Rail Pressure Sensor Circuit Performance * Fuel Delivery Error

The scan data available to view regarding the FRP sensor is: * Fuel Pressure (MPA) * Fuel Pressure Voltage

FUEL PRESSURE LIMITING VALVE

Also as we discussed earlier, the fuel pressure limiting valve on the Cummins 5.9L engine is located on top of the fuel rail next to the FRP sensor. On the Cummins 6.7L engine it is located in the end of the fuel rail.

The fuel pressure limiting valve is designed to protect the fuel system from over pressurization. Fuel pressure at the fuel rail is monitored by the fuel rail pressure sensor. If fuel pressure becomes excessive, the pressure limiting valve opens and vents excess pressure into the fuel drain circuit.

It is designed to open in a dual stage fashion at 28,282 psi (1,950 BAR). The second stage maintains pressure at 13,053 psi (900 BAR). When this happens, the FRP sensor will report to the ECM the pressure exceeded the maximum allowed and a DTC will be set. If this happens, it is a good idea to inspect the valve to determine if fuel is still leaking back into the return system. Simply disconnect the fuel line from the valve and crank the engine. If you observe any fuel coming from the valve, you either need to service the fuel rail, replace the valve or both.

Remember, the most common problems with the common rail injection system is contamination to the fuel system itself. These contaminant's can clog the fuel rail, increasing the pressure and tripping the valve. If contaminant's get into the valve it can cause the valve to pop and stay stuck open.

5.9L Pressure Limiting valve test courtesy Chrysler Corporation.

85 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

FUEL PRESSURE LIMITING VALVE

86 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

INJECTOR OPERATIONS

When we compare the injector from the 5.9L to the 6.7L engine, we are going to find some glaring differences. The most fundamental difference between the two injectors is that the 6.7L will have an IQA code that will need to be programmed into the ECU if you replace it.

As we discussed earlier, the Cummins 6.7L engine uses injectors that are IQA coded. Each fuel injector has a six-digit alphanumeric correction code. The correction code is printed on the intake side of the fuel injector and is used to identify injector calibration. When replacing any fuel injectors, this code must be entered into the vehicles Powertrain Control Module (PCM) using a diagnostic scan tool. In addition, if a new PCM is installed, use a diagnostic scan tool to program all six of the injector codes from the original fuel injectors into the new PCM.

AIR CHECK

When we analyze the ball and seat within a fuel injector, we will be looking for excessive fuel return coming from the ball and seat assembly itself. You can perform the fuel return test to determine if excessive fuel is returning to the system, but at the same time you can also apply high pressure air to the injector at the High Pressure Connection location.

When you apply high pressure air (clean shop air), via the high pressure connection, you should see no air leakage from the injector. If air leakage is indicated, you could very likely have an issue with the injector ball and seat assembly.

One other item to observe is the injector nozzle assembly. The performance of the injector is greatly determined by how clean this assembly is. This assembly can and will become full of debris as well as forming a “Carbon Ring” at the tip of the nozzle.

87 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

ECM INJECTOR CONTROL

As we discussed earlier, the ECM is responsible for injector control. The ECM controls the timing and activation of the injectors. Injector activation will vary between the 5.9L and the 6.7L. The 6.7L now needs to run post injection events in order to run a regeneration event when required.

On the 6.7L engine there are 2 pilot injector events, the main injection event and 2 post injection events. These post injection events only occur during regeneration events. The post injection will heat the catalyst hot enough to burn off soot in the DPF.

Again, the injectors on the 6.7L engine have a six digit alphanumeric correction code printed on the intake side of the injector. This code is called the Injector Quantity Adjustment (IQA) code and is used to identify the correct injector calibration.

HIGH PRESSURE FUEL LINE LEAK TESTING

High-pressure fuel lines deliver fuel (under pressure) of up to approximately 180,000 kPa (26,107 PSI) from the injection pump to the fuel injectors. The lines expand and contract from the high-pressure fuel pulses generated during the injection process. All high-pressure fuel lines are of the same length and inside diameter. Correct high-pressure fuel line usage and installation is critical to smooth engine operation.

6.7L high pressure fuel line diagnostics courtesy Chrysler Corporation.

88 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas

DIAGNOSIS OF THE COMMON RAIL INJECTION SYSTEM (RECAP)

Just to recap what we have already covered, as you diagnose common rail injection issues, it is important to go step by step.

The first step in our diagnostic procedure is to examine the lift pump pressure. The purpose of the lift pump is to supply (transfer) a low-pressure fuel source: from the fuel tank, through the fuel filter/water separator and to the fuel injection pump. Here, the low-pressure is raised to a high-pressure by the fuel injection pump for operation of the high-pressure fuel injectors. Check valves within the pump, control direction of fuel flow and prevent fuel bleed-back during engine shut down.

You will also want to monitor the actual fuel rail pressure versus the desired fuel rail pressure using your scan tool. This will help determine if the set point fuel pressure is met by the actual fuel rail pressure. The ECM will request a certain fuel pressure, (set point), and the actual fuel pressure must meet this in order to operate correctly. This is not negotiable. This is another item you would want to view during a road test. You need to see the actual fuel pressure parameter be equal to the desired fuel pressure under different load conditions.

The point to all of this is to build a structure to your diagnostic strategy. Start with the low pressure side, move to the high pressure side, then on to the return side.

89 CUMMINS 5.9L AND 6.7L ISSUES AND REVIEW OF OPERATION Presented by Tony Salas