GM Service Manual Online
For 1990-2009 cars only

Special Tools

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure

Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution in the Preface section.


    Object Number: 1777682  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Remove the connector position assurance (CPA) retainer (3).
  3. Disconnect the heated oxygen sensor (HO2S) electrical connector from the engine wiring harness electrical connector (2).

  4. Object Number: 1492088  Size: SH

    Caution: The oxygen sensor may be difficult to remove when the engine temperature is below 48°C (120°F). Excessive force may damage threads in the exhaust manifold or the exhaust pipe.

  5. Remove the HO2S (1) using the J 39194-B .

Installation Procedure


    Object Number: 1492088  Size: SH

    Note : 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.

  1. Coat the threads of the HO2S with anti-seize compound GM P/N 12377953 or equivalent, if necessary.
  2. Caution: Refer to Fastener Caution in the Preface section.

  3. Install the HO2S (1).
  4. Tighten
    Tighten the sensor to 42 N·m (31 lb ft) using the J 39194-B .


    Object Number: 1777682  Size: SH
  5. Connect the HO2S electrical connector to the engine wiring harness electrical connector (2).
  6. Install the CPA retainer (3).
  7. Lower the vehicle.