GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Notice: The Heated Oxygen Sensor (HO2S) and the Oxygen Sensor use a permanently attached pigtail and connector. Do not remove this pigtail from the Heated Oxygen Sensor. Damage or the removal of the pigtail or the connector could affect the proper operation of the sensor.

    Take care when handling the HO2S and the O2S. Keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants. Also avoid using cleaning solvents of any type. Do not drop the HO2S or the O2S. Do not roughly handle the HO2S or the O2S.

    Important: Bank 2 is the left bank.

  1. Turn the ignition OFF.
  2. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

  3. Object Number: 785791  Size: SH
  4. Disconnect the heated oxygen sensor (HO2S) electrical connector.
  5. Remove the HO2S wiring harness from the transmission case.
  6. Notice: Refer to Oxygen Sensor Notice in the Preface section.


    Object Number: 785783  Size: SH

    Important: Removal of the oxygen sensor is easier when the engine temperature is above 48°C (120°F).

  7. Remove the HO2S.

Installation Procedure

    Notice: Refer to Component Fastener Tightening Notice in the Preface section.

    Notice: A special anti-seize compound is used on the oxygen sensor threads. New service sensors should already have the compound applied to the threads. Coat the threads of a reused sensor with anti-seize compound P/N 5613695 or equivalent.


    Object Number: 785783  Size: SH
  1. Install the HO2S.
  2. Tighten
    Tighten the HO2S to 40 N·m (30 lb ft).


    Object Number: 785791  Size: SH
  3. Connect the HO2S electrical connector.
  4. Install the HO2S wiring harness to the transmission case.
  5. Lower the vehicle.