Chevrolet 12609949 Sensor Assembly, Heated Oxygen (Position 3)

You can Select Your Vehicle to check if 12609949 fits your vehicle.

The oxygen sensors require proper electrical connections, air circulation, operating temperature, and unleaded fuel for optimal operation.

All models are equipped with two oxygen sensors,a pre-converter oxygen sensor and a post-converter oxygen sensor. The pre-converter oxygen sensor measures the oxygen remaining in the exhaust gas after combustion, producing a voltage output that varies based on the oxygen content. The PCM continuously monitors this signal to determine the required fuel injector pulse width and maintain an air/fuel ratio of 14.7:1. The post-converter oxygen sensor, while not affecting the air/fuel ratio control, is used by the PCM to monitor the efficiency of the catalytic converter. The oxygen sensors require proper electrical connections, air circulation, operating temperature, and unleaded fuel for optimal operation. The PCM can detect sensor problems and set diagnostic trouble codes, causing it to revert to open-loop fuel control. When replacing an oxygen sensor, precautions should be taken to avoid damaging the sensor or its electrical connector. The post-converter sensor may require raising the vehicle, while the pre-converter sensor can be replaced without raising it. The sensor should be unscrewed using a suitable wrench or socket, and anti-seize compound should be applied to the threads before installation. Finally, the electrical connector should be reconnected and the vehicle lowered.