What are the common faults of oxygen sensors?
2 Answers
The common faults of oxygen sensors include ceramic breakage, filament burnout, and wire disconnection. Once these faults occur, the computer of the electronic fuel injection system cannot obtain the oxygen concentration information in the exhaust pipe, leading to increased engine fuel consumption and exhaust pollution, as well as engine issues such as unstable idle, misfire, and surging. Therefore, it is necessary to promptly troubleshoot or replace the faulty sensor. The automotive 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 the combustion quality of the engine fuel. The zirconia element in the oxygen sensor acts similarly to an electrolyte. Its working principle is based on utilizing the oxygen concentration difference between the inside and outside of the zirconia under certain conditions to generate a potential difference. The greater the concentration difference, the larger the potential difference.
Oxygen sensor failures are quite common. In my many years of car repair, I've seen quite a few owners come in with questions. The most common issues are sensor aging or contamination by carbon deposits, especially in cars that haven't had their oil changed for a long time. The dirt in the exhaust can clog the sensor, leading to inaccurate data. Circuit problems are also frequent, such as wire wear or loose connectors, which can cause intermittent signals. Then there's heater failure—since oxygen sensors need to preheat before starting, a broken heating element will render them completely non-functional. These faults can trigger the check engine light, cause a spike in fuel consumption, and even damage the catalytic converter. I recommend checking the sensor during regular maintenance; using an OBD scanner to read fault codes makes diagnosis quick. Also, avoid using low-quality gasoline, as this can effectively extend the sensor's lifespan.
