What are the causes of front and rear oxygen sensor failure?
3 Answers
Front and rear oxygen sensor failure can be caused by: 1. Poor fuel quality; 2. Faulty spark plugs; 3. Damaged catalytic converter. The effects of a faulty front oxygen sensor include: 1. Excessive exhaust emissions; 2. Deterioration of engine performance; 3. Engine stalling at idle; 4. Inaccurate engine operation and reduced power; 5. The engine control unit (ECU) cannot accurately determine the air-fuel mixture condition; 6. Impaired operation of the catalytic converter. The oxygen sensor is a critical feedback sensor in the fuel injection engine control system, playing a key role in controlling vehicle exhaust emissions, reducing environmental pollution, and improving fuel combustion quality in the engine. It is installed on the engine's exhaust pipe.
I've encountered oxygen sensor failures several times, and based on my experience, the most common issue is sensor aging and failure. After prolonged use, typically over 80,000 kilometers, the sensor may malfunction, especially in urban environments with frequent traffic congestion. Contamination is another major culprit - engine oil leaks or coolant seeping into the exhaust system can coat the sensor with oil residue or silicone-based sealant, clogging it completely. Physical damage is also a concern; driving on rough roads or accident-related vibrations can damage the sensor. Electrical failures are not uncommon either, with loose wiring harnesses or short circuits interrupting signals. My mechanic friends always remind me to pay attention to waterproofing and corrosion prevention during repairs. All these issues can lead to skyrocketing fuel consumption and excessive emissions. I recommend having technicians check sensor data with diagnostic equipment during regular maintenance.
After years of driving, I've found that most oxygen sensor failures stem from contamination buildup, oil or coolant leaking into the exhaust passage, or oil residue sticking to the sensor surface causing incorrect oxygen level readings. Physical impact is another common cause - I once cracked a sensor when reversing and scraping against a curb. Aging is also an issue; sensors typically need replacement after about ten years of use. Electrical problems like broken wiring or voltage fluctuations are frustrating too - my friend's check engine light came on recently for this reason. For prevention, avoid silicone-based sealants and regularly clean the sensor area to extend its lifespan. Ignoring these faults can increase fuel consumption by 10-20% and make exhaust fumes unbearable.
