GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.


    Object Number: 1256157  Size: SH
  1. Disconnect the negative battery cable.
  2. Notice: Refer to Heated Oxygen and Oxygen Sensor Notice in the Preface section.

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

    Notice: Remove oxygen sensors with the engine temperature above 48°C (120°F). Otherwise the oxygen sensors may be difficult to remove.

  3. Disconnect the O2S connector.
  4. Carefully remove the O2S from the exhaust manifold.

Installation Procedure


    Object Number: 1256158  Size: SH

    Important: A special anti-seize compound is used on the oxygen sensor threads. This compound consists of a liquid graphite and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New or serviced sensors will already have the compound applied to the threads. If a sensor is removed from any engine and is to be reinstalled, the threads must have an anti-seize compound applied before reinstallation.

  1. Coat the threads of the O2S with an anti-seize compound, if needed.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the O2S into the exhaust manifold.
  4. Tighten
    Tighten the oxygen sensor to 44 N·m (33 lb ft).

  5. Connect the O2S connector.
  6. Connect the negative battery cable.