GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 39194-C O2 Sensor Wrench

Removal Procedure


    Object Number: 932526  Size: SH

    Notice: The HO2S uses a permanently attached pigtail and connector. This pigtail should not be removed from the HO2S. Damage or removal of the pigtail or connector could affect proper operation of the sensor.

  1. Turn the ignition OFF.
  2. Caution: Ensure that the vehicle is properly supported and squarely positioned. To help avoid personal injury when a vehicle is on a hoist, provide additional support for the vehicle on the opposite end from which the components are being removed.

  3. Raise the vehicle.
  4. Disconnect the HO2S-2 harness connector.
  5. Remove the HO2S-2 harness clip from the heat shield attachment.
  6. Use a liquid penetrate before removing the sensor.
  7. Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section.

  8. Remove the HO2S-2 using the J 39194-C , or equivalent.

Installation Procedure


    Object Number: 932526  Size: SH

    Notice: Silicone based products will contaminate the HO2S. Use only a nickel based anti-seize compound that does not contain silicone.

  1. Apply a small amount of anti-seize compound Saturn P/N 21485279, or equivalent, to the threads of the HO2S-2.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the HO2S-2 using the J 39194-C , or equivalent.
  4. Tighten
    Tighten the HO2S-2 sensor-to-exhaust pipe to 45 N·m (33 lb ft).

    Notice: Do Not apply any material in the HO2S-2 harness connector such as grease or dielectric compound. The wires carry air reference to the sensor in order for the sensor to operate properly.

  5. Install the HO2S-2 harness clip to the heat shield attachment bolt.
  6. Tighten
    Tighten the bolt to 4 N·m (35 lb in).

  7. Connect the HO2S-2 harness connector. Push in the connector until a click is heard, then pull back to confirm a positive engagement.
  8. Ensure the HO2S-2 harness pigtail connector is secure to the chassis.