Q: How Does the Oxygen Sensor in the Exhaust System Work?
A: The oxygen sensor in the exhaust system reacts with the elements to produce a voltage output that varies based on the amount of oxygen in the exhaust. This feedback signal is used by the PCM to determine the required fuel injector pulse width and control the air/fuel ratio. The ideal ratio for emissions, fuel economy, and engine performance is 14.7:The post-converter oxygen sensor monitors the efficiency of the Catalytic Converter. The configuration of the oxygen sensor varies depending on the model and emissions package. The sensor operates correctly when there are good electrical connections, proper air circulation, correct operating temperature, and unleaded fuel. The PCM can detect sensor problems and set Diagnostic Trouble Codes. To replace the sensor, raise the vehicle, locate the sensor and disconnect it, remove the sensor using a wrench or socket, clean the threads, and apply anti-seize compound if necessary. Installation is the reverse of removal.