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.

Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section.


    Object Number: 1923753  Size: SH
  1. Remove the connector position assurance (CPA) retainer from the heated oxygen sensor (HO2S) connection.
  2. Disconnect the engine wiring harness electrical connector (2) from the HO2S electrical connector (1).
  3. Remove the HO2S electrical connector (1) clip from the transmission fluid fill tube bracket.
  4. Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.


    Object Number: 1923757  Size: SH
  5. Remove the HO2S (1). Use the J 39194-B , if required.

Installation Procedure

Important: A special anti-seize compound is used on the HO2S threads. The compound consists of liquid graphite and glass beads. The graphite tends to burns away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an exhaust component and if for any reason the sensor is to be reinstalled, the threads must have anti-seize compound applied before reinstallation.


    Object Number: 1923757  Size: SH
  1. If reinstalling the old sensor, coat the threads with the anti-seize compound P/N 12377953, or equivalent.
  2. Notice: Refer to Component Fastener Tightening Notice in the Preface section.

  3. Install the HO2S (1) . Use the J 39194-B , if required.
  4. Tighten
    Tighten the HO2S to 42 N·m (31 lb ft).


    Object Number: 1923753  Size: SH
  5. Connect the engine wiring harness electrical connector (2) to the HO2S electrical connector (1).
  6. Install the HO2S electrical connector (1) clip to the transmission fluid fill tube bracket.
  7. Install the CPA retainer to the HO2S connection.