SENSORS IN AUTOMOBILES INTERNAL COMBUSTION ENGINES SENSORS Author Dr. Osama Mohammed Elmardi Suleiman Khayal Department of Mechanical Engineering, Faculty of Engineering and Technology Nile Valley University Atbara – Sudan August 2020 i Dedication In the name of Allah, the merciful, the compassionate All praise is due to Allah and blessings and peace is upon his messenger and servant, Mohammed, and upon his family and companions and whoever follows his guidance until the day of resurrection. To the memory of Professor Sabir Mohammed Salih, Professor Elfadil Adam Abdallah, Associate Professor Mohi- Eldin Idris Harba, Associate Professor Hashim Ahmed Ali, Associate Professor Abdel-Jaleel Yousef, Lecturer Ishraga Salih, Lecturer Intisar Abdu and Associate Professor Salah Ahmed Ali who they taught me the greatest value of hard work and encouraged me in all our endeavors. This textbook is dedicated mainly to undergraduate engineering students, especially mechanical, and production engineering students where most of the applications presented are focused on the necessity and importance of using sensors in automobiles, which includes how fuel injection system works, crankshaft position sensor, cylinder head temperature gauge, internal combustion engine cooling, exhaust gas temperature gauge, idle air control actuator, engine knocking, manifold absolute pressure sensor (MAP), mass flow sensor, nitrogen oxide sensor, oxygen sensor, and throttle position sensor. ii The present textbook presents a brief outline of the usage and functions of automobile sensors. Engine sensors in a vehicle are incorporated to provide the correct amount of fuel for all operating conditions. A large number of input sensors are monitored by the engine control unit. Today, sensor technology has become common in modern vehicles. Sensors enhance safety of the people - both on board and on road, control vehicle emissions and make vehicles more efficient. In this article, we will discuss different types of engine sensors used in modern vehicles. Last but not least, may Allah accepts this humble work and i hope that it will be beneficial to its readers. iii Acknowledgements I am grateful and deeply indebted to Mechanical Engineer Professor Dr. Mahmoud Yassin Osman for his close supervision, consultation and constructive criticism, without which this work would not have been accomplished. I am also indebted to many people. Published texts in the necessity and importance of using sensors in automobiles have been contributed to the author’s thinking. The present study has been taken from the point of view of how fuel injection system works, crankshaft position sensor, cylinder head temperature gauge, internal combustion engine cooling, exhaust gas temperature gauge, idle air control actuator, engine knocking, manifold absolute pressure sensor (MAP), mass flow sensor, nitrogen oxide sensor, oxygen sensor, and throttle position sensor. Members of Mechanical Engineering Department at Faculty of Engineering and Technology, Nile Valley University - Atbara have served to sharpen and refine the treatment of the topics. The author is extremely grateful to them for constructive criticisms and valuable suggestions. The author would like to acknowledge with deep thanks and gratitude the moral and financial support extended to them by Nile Valley University via its Faculty of Engineering and Technology despite its financial hardships. My thanks is extended to Professor Mohammed Ibrahim Shukri for giving his great experience in writing reports, iv researches and books according to the standard format, and also for revising several times the manuscript of the present book. Special gratitude is due to Professor Mahmoud Yassin Osman for continuous follow up step by step the completion of this textbook and the greatest advice he has given in writing sequentially the various chapters of this book. I express my profound gratitude to Mr. Osama Mahmoud Mohammed Ali of Dania Center for Computer and Printing Services, Atbara, and engineer Awad Ali Bakri who they spent many hours in editing, re – editing and correcting the manuscript. Finally i would like to acknowledge the generous assistance of the staff at different levels working in the industrial liaison and consultancy unit, Atbara and the mechanical and production engineering departments' staff working in the different workshops and laboratories in the Faculty of Engineering and Technology, Atbara. v Contents Description Page Dedication ii Acknowledgements iv Contents vi Preface x Chapter One How Fuel Injection System Works 1.1 Introduction 1 1.2 Mass Airflow Sensor 2 1.3 Oxygen Sensor 3 1.4 Throttle Position Sensor 3 1.5 Coolant Temperature 4 Sensor 1.6 Voltage Sensor 4 1.7 Manifold Absolute 5 Pressure Sensor 1.8 Engine Speed Sensor 5 Chapter Two Crankshaft Position Sensor 2.1 Introduction 7 2.2 Types of Sensor 8 2.3 Function of Sensor 8 Chapter Three Cylinder Head Temperature 10 Gauge Chapter Four Internal Combustion Engine vi Cooling 4.1 Introduction 13 4.2 Overview 14 4.3 Basic Principles 15 4.4 Generalization 20 Difficulties 4.5 Further Information on 21 Air-Cooled Engine 4.6 Liquid Cooling (Radiator 23 Engine Cooling) Chapter Five Exhaust Gas Temperature Gauge 5.1 Introduction 27 5.2 Applications 27 5.3 Oxygen Sensor 28 5.4 Advanced Tuning 28 Chapter Six Idle Air Control Actuator 6.1 Introduction 30 6.2 Description 30 6.3 Problems with IAC 31 Chapter Seven Engine Knocking 7.1 Introduction 32 7.2 Normal Combustion 32 7.3 Abnormal Combustion 33 7.4 Knock Detection 37 7.5 Knock Prediction 38 vii 7.6 Knock Control 38 Chapter Eight MAP Sensor 8.1 Introduction 40 8.2 Example 41 8.3 Varying RPM and 42 Engine Loads 8.4 Vacuum Comparison 42 8.5 EGR Testing 42 8.6 Common Confusion with 43 Boost Sensors and Gauges Chapter Nine Mass Flow Sensor 9.1 Introduction 45 9.2 Moving Vane Meter 46 9.3 Hot Wire Sensor (MAF) 48 9.4 Cold Wire Sensor 50 9.5 Kármán Vortex Sensor 52 9.6 Membrane Sensor 53 9.7 Laminar Flow Elements 54 Chapter Ten Nitrogen Oxide Sensor 10.1 Introduction 55 10.2 Overview 55 10.3 Challenges 56 Chapter Eleven Oxygen Sensor 11.1 Introduction 58 11.2 Automotive 59 Applications viii 11.3 Function of a Lambda 63 Probe 11.4 The Probe 63 11.5 Operation of the Probe 64 11.6 Location of the Probe in 69 a System 11.7 Sensor Surveillance 69 11.8 Sensor Failures 69 11.9 Diving Applications 71 11.10 Scientific Applications 72 Chapter Twelve Throttle Position Sensor 76 References 78 Author Brief Auto - 85 Biography ix Preface Sensors are essential components of automotive electronic control systems. Sensors are defined as “devices that transform (or transduce) physical quantities such as pressure or acceleration (called measurands) into output signals (usually electrical) that serve as inputs for control systems". It wasn’t that long ago that the primary automotive sensors were discrete devices used to measure oil pressure, fuel level, coolant temperature, etc. Starting in the late1970s, microprocessor-based automotive engine control modules were phased into satisfy federal emissions regulations .These systems required new sensors such as MAP (manifold absolute pressure), air temperature, and exhaust-gas stoichiometric air-fuel-ratio operating point sensors. The need for sensors is evolving and is progressively growing. For example, in engine control applications, the number of sensors used will increase from approximately ten in1995, to more than thirty in 2010. Automotive engineers are challenged by a multitude of stringent requirements. For example, automotive sensors typically must have combined/total error less than 3% over their entire range of operating temperature and measurands change, including all measurement errors due to nonlinearity. Engine sensors in a vehicle are incorporated to provide the correct amount of fuel for all operating conditions. A large number of input sensors are monitored by the engine control unit. Today, sensor technology has become common in modern vehicles. Sensors enhance safety of the people - both on board and on road, control vehicle emissions and make x vehicles more efficient. In this article, we will discuss different types of engine sensors used in modern vehicles. The aim of the present textbook was to review the importance of using sensors in automobiles from different points of view which include how fuel injection system works, crankshaft position sensor, cylinder head temperature gauge, internal combustion engine cooling, exhaust gas temperature gauge, idle air control actuator, engine knocking, manifold absolute pressure sensor (MAP), mass flow sensor, nitrogen oxide sensor, oxygen sensor, and throttle position sensor. Chapter one which is entitled as how fuel injection system works constitutes introduction to sensors used in automobiles, mass airflow sensor, oxygen sensor, throttle position sensor, coolant temperature sensor, voltage sensor, manifold absolute pressure sensor and engine speed sensor. Engine sensors in a vehicle are incorporated to provide the correct amount of fuel for all operating conditions. A large number of input sensors are monitored by the engine control unit. Today, sensor technology has become common in modern vehicles. Sensors enhance safety of the people - both on board and on road, control vehicle emissions and make vehicles more efficient. In this article, we will discuss different types of engine sensors used in modern vehicles. Chapter two which is entitled crankshaft position sensor includes introduction, types of sensors, and function of sensor. A crank sensor is an electronic device used in an internal combustion engine, both petrol and xi diesel, to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control the fuel injection or the ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on petrol engines. The crank sensor can be used in combination with a similar camshaft position sensor to monitor the relationship between the pistons and valves in the engine, which is particularly important in engines with variable valve timing.