Why should you change an ?

It is critical that oxygen are replaced at the How to diagnose suggested intervals provided by manufacturers before the sensor fails. Following the State of oxygen sensor: recommendations will prevent long term damage to a Greenish, grainy discoloration. Possible cause: vehicle’s engine, reduce harmful (CO2) has escaped and entered the . emissions and save money when refueling your vehicle. Measure: Replace the oxygen sensor. Check the , head, An oxygen sensor’s service life varies: oxygen sensors manifold and head for wear and cracks. with 1 – 2 wires have a typical service life between 30,000 – 50,000 miles; while 3 – 5 wire sensors have a

life span of up to 100,000 miles. Checking and State of oxygen sensor: Blackened, with oily contamination. replacing worn out oxygen sensors has become a Possible cause: critical part of regular vehicle maintenance. Excessive oil consumption. Measure: Check the valve guides and seals, which may be worn. Replace the A worn out oxygen sensor can cause oxygen sensor.

ff Engine performance issues

ff Lower miles per gallon fuel efficiency State of oxygen sensor: Dark brown discoloration. ff Excessive harmful exhaust emissions Possible cause: Air-fuel mixture too rich. ff damage Measure: Check the fuel pressure. Replace the oxygen sensor. Replacing a worn oxygen sensor

ff Improves engine performance

ff Reduces harmful emissions State of oxygen sensor: Reddish or white discoloration. Possible cause: ff Optimizes fuel delivery for maximum Fuel additives in the . miles per gallon Measure: Do not use fuel additives. Replace the oxygen sensor. ff Prevents catalytic converter failure

Oxygen sensors are important engine components – State of oxygen sensor: Broken cable. indispensable for reliable Possible cause: engine function and correct Excessive cable tension. emission values. But the Measure: Replace the oxygen sensor. perfect functioning of oxygen Route the new cable without tension. sensors can be jeopardized by many factors:

ff Environmental influences, such as salt and dirt State of oxygen sensor: The molded cable tubing is damaged. ff Large temperature fluctuations Possible cause: Impact by stone chippings. ff Poor-quality fuel Measure: Replace the oxygen sensor.

ff Soot and oil residues in the exhaust

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