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For 1990-2009 cars only

Heated Oxygen Sensor Replacement HO2S1

Tools Required

J 39194-B Heated Oxygen Sensor Socket

Removal Procedure

The heated oxygen sensor (HO2S 1) may be difficult to remove when engine temperature is less than 48°C (120°F). Excessive force may damage the threads in the exhaust manifold.

  1. Turn OFF the ignition.

  2. Object Number: 73896  Size: SH
  3. Disconnect the HO2S 1.
  4. Important : A special anti-seize compound is used on the HO2S 1 threads. The compound consists of graphite suspended in fluid and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or service sensors will already have the compound applied to the threads. If a sensor is removed from an engine and is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

  5. Using a J 39194-B heated oxygen sensor socket, carefully back out the heated oxygen sensor.

Installation Procedure


    Object Number: 73896  Size: SH
  1. Coat the threads of the HO2S 1 with anti-seize compound GM P/N 5613695, or an equivalent, if necessary.
  2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the HO2S 1.
  4. Tighten
    Tighten the sensor to 41 N·m (30 lb ft).

  5. Connect the H02S 1.

Heated Oxygen Sensor Replacement HO2S2

Tools Required

J 39194-B Heated Oxygen Sensor Socket

Removal Procedure

The heated oxygen sensor (HO2S 2) may be difficult to remove when engine temperature is less than 48°C (120°F). Excessive force may damage the threads in the exhaust pipe.

  1. Turn OFF the ignition.

  2. Object Number: 10975  Size: SH
  3. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  4. Disconnect the HO2S 2.
  5. Important : A special anti-seize compound is used on the HO2S 2 threads. The compound consists of graphite suspended in fluid and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or service sensors will already have the compound applied to the threads. If a sensor is removed from an engine and is to be reinstalled, the threads must have anti-seize compound applied before reinstallation.

  6. Using the J 39194-B heated oxygen sensor socket, carefully back out the HO2S 2.

Installation Procedure


    Object Number: 10975  Size: SH
  1. Coat the threads of the HO2S 2 with anti-seize compound GM P/N 25613695, or an equivalent, if necessary.
  2. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Using the J 39194-B heated oxygen sensor socket install the HO2S 2.
  4. Tighten
    Tighten the sensor to 41 N·m (30 lb ft).

  5. Connect the H02S 2 sensor.
  6. Lower the vehicle.