Automotive Engineering;  electronically controlled engine;  Oxygen sensor;  three-way catalytic converter;  emissions;  Conversion efficiency

The influence of common faults of electronically controlled engine oxygen sensors on engine emissions and conversion efficiency of three-way catalytic converters was studied on the engine fault simulation test bench. The results show that if the oxygen sensor is disconnected, the fuel injection pulse width and emission of the engine remain basically unchanged for the idle condition. For common working conditions, the power of the engine increases slightly, fuel consumption increases more, CO and HC emissions increase, and NOx emissions decrease. If the exhaust hole of the oxygen sensor is blocked, the performance change of the engine is similar to the disconnection fault of the oxygen sensor. The concentration of exhaust pollutants before and after the three-way catalytic converter can be detected separately, and the performance of the three-way catalytic converter can be judged. Under common working conditions, if the conversion efficiency of the three-way catalytic converter is low, the three-way catalytic converter is replaced by replacing the new oxygen sensor