GM Service Manual Online
For 1990-2009 cars only

Tools Required

SA9603E Oxygen Sensor Wrench Remover/Installer

Removal Procedure

    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.

  1. Raise the vehicle.

  2. Object Number: 871569  Size: SH

    Notice: Do not apply grease or silicon products to the heated oxygen sensor (H02S-2). Do not alter the wiring in any way. The wires carry air reference to the sensor.

  3. Remove the HO2S-2 wiring harness from the frame by pushing up on the retaining clip tab.

  4. Object Number: 871572  Size: SH
  5. Remove the connector position assurance (CPA) device and disconnect the HO2S-2 harness connector.

  6. Object Number: 871580  Size: SH
  7. Remove the HO2S-2 wiring harness from the trough in the converter heat shield by gently pulling the wiring harness from its retaining clips.
  8. Important: The HO2S-2 uses a permanently attached pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector will affect proper operation of the sensor.

  9. Remove the HO2S-2 using the SA9603E . If necessary, use a liquid penetrate before removing the sensor.

Installation Procedure


    Object Number: 871582  Size: MF

    Notice: When reinstalling an existing sensor, always use an anti-seize compound (Saturn P/N 21485279 or equivalent) on the threads of the oxygen sensor. Never use silicone products. They will contaminate the sensor. A new Saturn service replacement sensor already has a sufficient amount of anti-seize compound and does not require any additional compound to be added.

  1. Install the HO2S-2 using the SA9603E .
  2. Tighten
    Tighten the oxygen sensor-to-exhaust manifold 45 N·m (33 lb ft).


    Object Number: 871584  Size: MH

    Important: Ensure the marker tape is centered with the edge of the trough to ensure enough slack in the harness.

  3. Install the HO2S-2 harness into the retaining clips in the trough in the converter heat shield.

  4. Object Number: 871572  Size: SH
  5. Connect the HO2S-2 harness connector. Push in the connector until a click is heard and pull back to confirm a positive engagement.
  6. Install the connector position assurance (CPA) device in the harness connector.

  7. Object Number: 871590  Size: SH
  8. Install the HO2S-2 wiring harness retaining clip into the cradle.
  9. Lower the vehicle to start the engine.
  10. Check for leaks.