What problems can an oxygen sensor failure cause?

[Ellie]

Problems caused by oxygen sensor failure include: reduced vehicle power, difficulty in acceleration, unstable idle speed during operation, increased fuel consumption, excessive vehicle pollutant emissions, spark plug failure, and fuel supply system failure. When the oxygen sensor fails, the ECU cannot obtain information about the oxygen concentration in the exhaust pipe, and thus cannot provide feedback control on the mixture concentration. In engines equipped with a three-way catalytic converter to reduce exhaust pollution, the oxygen sensor is an essential component. Since the purification ability of the three-way catalyst for CO, HC, and NOx drops sharply once the air-fuel ratio of the mixture deviates from the theoretical air-fuel ratio, an oxygen sensor is installed in the exhaust pipe to detect the oxygen concentration in the exhaust and send a feedback signal to the ECU. The ECU then adjusts the fuel injection volume of the injector to keep the air-fuel ratio of the mixture near the theoretical value.