Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 1500 Series

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. Unbolt the front propeller shaft from the front differential, if equipped with four wheel drive (4WD). Refer to Front Propeller Shaft Replacement .
3. For vehicles equipped with a 4L60-E/4L70-E automatic transmission perform the following steps, for vehicles equipped with a 6L80-E automatic transmission proceed to step 7.
4. Remove the connector position assurance (CPA) retainer.
5. Disconnect the engine wiring harness electrical connector (2) from the HO2S.
6. Remove the HO2S electrical connector clip (1) from the fuel line clip.



7. Remove the CPA retainer (2).
8. Remove the engine wiring harness electrical connector clip (1) from the fuel line clip.
9. Disconnect the engine wiring harness electrical connector (3) from the HO2S.

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




10. Remove the HO2S (1 or 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: Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

2. Install the HO2S (1 or 2).

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




3. For vehicles equipped with a 4L60-E/4L70-E automatic transmission perform the following steps, for vehicles equipped with a 6L80-E automatic transmission proceed to step 7.
4. Install the HO2S electrical connector clip (1) to the fuel line clip.
5. Connect the engine wiring harness electrical connector (2) to the HO2S.
6. Install the CPA retainer.



7. Connect the engine wiring harness electrical connector (3) to the HO2S.
8. Install the engine wiring harness electrical connector clip (1) to the fuel line clip.
9. Install the CPA retainer (2).
10. Install the front propeller shaft to the front differential, if equipped with 4WD. Refer to Front Propeller Shaft Replacement .
11. Lower the vehicle.

Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 2500 Series

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. Unbolt the front propeller shaft from the front differential, if equipped with four wheel drive (4WD). Refer to Front Propeller Shaft Replacement .
3. Remove the connector position assurance (CPA) retainer (2).
4. Disconnect the HO2S electrical connector from the engine wiring harness electrical connector (3).

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




5. Remove the HO2S (1).

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: Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

2. Install the HO2S (1).

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




3. Connect the HO2S electrical connector to the engine wiring harness electrical connector (3).
4. Install the CPA retainer (2).
5. Install the front propeller shaft to the front differential, if equipped with 4WD. Refer to Front Propeller Shaft Replacement .
6. Lower the vehicle.