Oxygen Sensor: Description and Operation

The front Oxygen Sensor is mounted in the exhaust system in front of the warm-up Catalytic Converter so it can monitor the oxygen content of the exhaust gases leaving the Engine. By constantly monitoring the voltage output of the Heated Oxygen Sensor, the ECM calculates the fuel mixture correction to the injector pulse width.

To activate the sensor faster and lower emissions, a heated Oxygen Sensor is incorporated. Additionally, the rear heated Oxygen Sensor is installed downstream of the warm-up catalytic converter for catalyst monitoring.