GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 39194-B Heated Oxygen Sensor Wrench

Notice: When replacing the HO2S perform the following:

   • A code clear with a scan tool, regardless of whether or not a DTC is set
   • HO2S heater resistance learn reset with a scan tool, where available
Perform the above in order to reset the HO2S resistance learned value and avoid possible HO2S failure.

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

Removal Procedure


    Object Number: 1771748  Size: SH
  1. Remove the connector position assurance (CPA) retainer.
  2. Disconnect the engine wiring harness electrical connector (1) from the heated oxygen sensor (HO2S) electrical connector.
  3. Notice: Refer to Excessive Force and Oxygen Sensor Notice in the Preface section.

  4. Using the J 39194-B remove the HO2S (2) from the exhaust manifold.

Installation Procedure

Important: Use special anti-seize compound on the HO2S threads. The compound consists of graphite suspended in fluid and glass beads. The graphite burns away, but the glass beads remain, making the sensor easier to remove. New service sensors already have the compound applied to the threads. If you remove an oxygen sensor and if for any reason you must install the same oxygen sensor, apply the anti-seize compound to the threads before reinstallation.


    Object Number: 1771748  Size: SH
  1. Coat the threads of the HO2S with the anti-seize compound P/N 5613695, or equivalent if necessary.
  2. Notice: Refer to Component Fastener Tightening Notice in the Preface section.

  3. Using the J 39194-B , install the HO2S (2) into the exhaust manifold.
  4. Tighten
    Tighten the HO2S to 42 N·m (31 lb ft).

  5. Connect the engine wiring harness electrical connector (1) to the HO2S electrical connector.
  6. Install the CPA retainer.