What are the effects of a faulty oxygen sensor?
4 Answers
Oxygen sensor failure can lead to decreased engine power and increased fuel consumption. The oxygen sensor detects the oxygen content in the exhaust and feeds this data back to the ECU, allowing the ECU to adjust the air-fuel ratio accordingly. The oxygen sensor is installed near the three-way catalytic converter, with one sensor positioned in front of it and another behind it. As a standard component in automobiles, the oxygen sensor uses ceramic sensitive elements to measure the oxygen potential in the exhaust pipe. Based on chemical equilibrium principles, it calculates the corresponding oxygen concentration to monitor and control the combustion air-fuel ratio, ensuring product quality and compliance with exhaust emission standards.
If the oxygen sensor fails, it's a real headache. As a taxi driver with over 20 years of experience, I've seen this issue countless times. It's like the engine's nose stops working, unable to detect the oxygen levels in the exhaust. As a result, the ECU blindly injects fuel, and fuel consumption can spike by 30% or more. Last time my car had this problem, it burned an extra 4 liters per 100 km – a real pain on long trips. Plus, the exhaust smells terrible, and it will definitely fail the annual inspection. The worst part is it can easily damage the catalytic converter, and replacing a new one costs over 2,000 yuan. My advice is to get it checked as soon as the engine warning light comes on, especially for older cars which are more prone to this issue.
Last month, my car's oxygen sensor just failed, and it was such a headache. I could clearly feel the car lacked power, and even when I floored the accelerator, the speed increased sluggishly. Originally, a full tank could last 500 kilometers, but now I had to find a gas station after just over 400 kilometers. The mechanic said if I continued driving like this, the hydrocarbon concentration in the exhaust could exceed the standard by more than ten times, and the catalytic converter might even melt. Later, I spent 500 to replace it, and the dashboard warning light went off the next day. Now, every time I start the car, I subconsciously check the exhaust color, afraid it might act up again.
The most annoying thing about a faulty oxygen sensor is the sudden surge in fuel consumption. As a rideshare driver, I've experienced it firsthand—what used to be 30 trips on a 300-yuan gas fill now barely covers 25. The repair shop owner explained it controls the air-fuel ratio; when broken, gasoline burns inefficiently. It also triggers the check engine light, guaranteeing a fail on annual emissions tests. Prolonged neglect worsens things, potentially causing spark plug carbon buildup or even cylinder scoring. Just last week, I replaced it with a Bosch sensor, costing 700 yuan including labor. My advice? Don't delay—fixing it early saves money long-term.
