Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
2. Remove the connector position assurance (CPA) retainer (3).
3. Disconnect the engine wiring harness electrical connector (2) from the HO2S electrical connector (1).
4. Remove the HO2S clip from the engine wiring harness clip (4).

Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.




5. Remove the HO2S (2).

Important: A special anti-seize compound is used on the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.

Notice: Refer to Component Fastener Tightening Notice in the Preface section.

2. Install the HO2S (2).

Tighten
Tighten the sensor to 42 N·m (31 lb ft).




3. Connect the engine wiring harness electrical connector (2) to the HO2S electrical connector (1).
4. Install the CPA retainer (3).
5. Install the HO2S clip to the engine wiring harness clip (4).
6. Lower the vehicle.