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For 1990-2009 cars only

Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 1500 Series

Removal Procedure

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


    Object Number: 1704005  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the connector position assurance (CPA) retainer (1).
  3. Disconnect the HO2S electrical connector from the engine wiring harness electrical connector (3).
  4. Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.


    Object Number: 1704008  Size: SH
  5. Remove the HO2S (5).

Installation Procedure

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.


    Object Number: 1704008  Size: SH
  1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
  2. 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.

  3. Install the HO2S (5).
  4. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).


    Object Number: 1704005  Size: SH
  5. Connect the HO2S electrical connector to the engine wiring harness electrical connector (3).
  6. Install the CPA retainer (1).
  7. Lower the vehicle.

Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 2500 Series

Removal Procedure

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


    Object Number: 1704005  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the connector position assurance (CPA) retainer (1).
  3. Disconnect the HO2S electrical connector from the engine wiring harness electrical connector (3).
  4. Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.


    Object Number: 1851870  Size: SH
  5. Remove the HO2S (4).

Installation Procedure

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.


    Object Number: 1851870  Size: SH
  1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
  2. 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.

  3. Install the HO2S (4).
  4. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).


    Object Number: 1704005  Size: SH
  5. Connect the HO2S electrical connector to the engine wiring harness electrical connector (3).
  6. Install the CPA retainer (1).
  7. Lower the vehicle.

Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 2500 Series - Cab/Chassis

Removal Procedure

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


    Object Number: 1856442  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the HO2S electrical connector rosebud clip from the engine wiring harness clip.
  3. Remove the connector position assurance (CPA) retainer (8).
  4. Disconnect the HO2S electrical connector (3) from the engine wiring harness electrical connector (4).
  5. Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.


    Object Number: 1856443  Size: SH
  6. Remove the HO2S (4).

Installation Procedure

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.


    Object Number: 1856443  Size: SH
  1. If reinstalling the old sensor, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.
  2. 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.

  3. Install the HO2S (4).
  4. Tighten
    Tighten the sensor to 42 N·m (31 lb ft).


    Object Number: 1856442  Size: SH
  5. Connect the HO2S electrical connector (3) to the engine wiring harness electrical connector (4).
  6. Install the CPA retainer (8).
  7. Install the HO2S electrical connector rosebud clip to the engine wiring harness clip.
  8. Lower the vehicle.