GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

Removal Procedure

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


    Object Number: 1239005  Size: SH

    Important: 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. Disconnect the heated oxygen sensor (HO2S) 1 electrical connector.
  2. Use the J 39194-B to remove the HO2S 1.

Installation Procedure


    Object Number: 1239005  Size: SH

    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.

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

  3. Install the HO2S 1.
  4. Tighten
    Use the J 39194-B to tighten the sensor to 41 N·m (30 lb ft).

  5. Connect the H02S 1 electrical connector.