GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Important: The HO2S may be difficult to remove when the engine temperature is below 48°C (120°F). Excessive force may damage the threads in the exhaust manifold or exhaust pipe. It may be necessary to lower the exhaust system to gain sufficient access to a HO2S and/or a HO2S connector.

  1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  2. Object Number: 710393  Size: SH
  3. Disconnect the HO2S electrical connector (1).

  4. Object Number: 710400  Size: SH
  5. Carefully back out the HO2S (3).

Installation Procedure

Important:: A special anti-seize compound is used on the HO2S 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 if for any reason is to be reinstalled, the threads must have anti-seize compound applied before reinstallation.

  1. Coat the threads of the HO2S with anti-seize compound P/N 5613695, or equivalent if necessary.

  2. Object Number: 710400  Size: SH

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


    Object Number: 710393  Size: SH
  5. Connect the HO2S electrical connector (4).
  6. Lower the vehicle.