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: 1777179  Size: SH
  1. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  2. Remove the connector position assurance (CPA) retainer (3).
  3. Disconnect the engine wiring harness electrical connector (2) from the heated oxygen sensor (HO2S) electrical connector.
  4. Remove the HO2S electrical connector rosebud clip (1) from the ignition coil bracket.

  5. Object Number: 1585927  Size: SH

    Notice: 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.

  6. Remove the HO2S using the J 39194-B .

Installation Procedure


    Object Number: 1585927  Size: SH

    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 is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.

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

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


    Object Number: 1777179  Size: SH
  5. Connect the engine wiring harness electrical connector (2) to the HO2S electrical connector.
  6. Install the CPA retainer (3).
  7. Install the HO2S electrical connector rosebud clip (1) to the ignition coil bracket.
  8. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement .