GM Service Manual Online
For 1990-2009 cars only

Heated Oxygen Sensor Replacement Front

Removal Procedure

Notice: Remove oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.

Notice: Take care when handling oxygen sensors. The electrical connector and louvered end must be kept free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

  1. Raise and support the vehicle.
  2. Remove the front splash shield.
  3. Disconnect the front oxygen sensor connector.
  4. Remove the front oxygen sensor from the front exhaust manifold.

Installation Procedure

Notice: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.

  1. Install the front oxygen sensor in the front exhaust manifold.
  2. Tighten
    Tighten the front HO2S sensor to 41 N·m (30 lb ft). Refer to

    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.

    in general information.

  3. Connect the front oxygen sensor connector.
  4. Install the front splash shield.
  5. Lower the vehicle.

Heated Oxygen Sensor Replacement Rear

Removal Procedure

Notice: Remove oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.

Notice: Take care when handling oxygen sensors. The electrical connector and louvered end must be kept free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

  1. Raise and support the vehicle.
  2. Support rear of powertrain frame.
  3. Remove four frame bolts (#2 and #3 locations).
  4. Lower the frame no more than 3 inches.
  5. Disconnect the rear oxygen sensor connector.
  6. Remove the rear oxygen sensor from the rear exhaust manifold.

Installation Procedure

Notice: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.

  1. Install the rear oxygen sensor in the rear exhaust manifold.
  2. Tighten
    Tighten the rear HO2S sensor to 41 N·m (30 lb ft). Refer to

    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.

    in general information.

  3. Connect the rear oxygen sensor connector.
  4. Raise the frame.
  5. Install the four frame bolts (#2 and #3 locations).
  6. Tighten
    Tighten the frame bolts to 100 N·m (74 lb ft). Refer to

    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.

    in general information.

  7. Lower the vehicle.

Heated Oxygen Sensor Replacement Pre- and Post-Converter

Removal Procedure

Notice: Remove oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.

Notice: Take care when handling oxygen sensors. The electrical connector and louvered end must be kept free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

  1. Raise and support the vehicle.
  2. Disconnect the pre- or post-converter oxygen sensor connector.
  3. Remove the pre- or post-converter oxygen sensor.

Installation Procedure

Notice: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.

  1. Install the pre- or post-converter oxygen sensor.
  2. Tighten
    Tighten the Pre or Post HO2S sensor to 41 N·m (30 lb ft). Refer to

    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.

    in general information.

  3. Connect the pre- or post-converter oxygen sensor connector.
  4. Lower the vehicle.