1.The engine fault light is on:
If the oxygen sensor fails, the engine fault light on the instrument panel may illuminate. This is one of the common indicators. The faulty sensor cannot directly trigger the warning light by itself, but it can lead to other faults in the vehicle system, resulting in the illumination of the engine inspection light. Since the illuminated engine light can indicate various engine component failures, it is advisable to take the car to a repair shop to run an OBDII diagnostic scanner and obtain an error code.
2.Instant idle speed or insufficient engine power, slow acceleration, and frequent misfires:
If you observe any abnormalities such as frequent misfires, rough idling, or reduced engine performance, it may indicate oxygen sensor failure. Other issues resulting from oxygen sensor failure include decreased power, engine hesitation, and stalling when starting the car. Unexplained sluggishness in vehicle performance is also a significant indicator. It is important to promptly stop driving the vehicle, replace the oxygen sensor, and address any engine repairs needed.