GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Warning: Refer to Oxygen Sensor Caution in the Preface section.


    Object Number: 1240894  Size: SH
  1. Remove the air cleaner/resonator assembly. Refer to Air Cleaner Assembly Replacement.
  2. Remove the exhaust manifold heat shield.
  3. Disconnect the oxygen sensor connector.
  4. Caution: 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.

  5. Remove the oxygen sensor.

Installation Procedure

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1240894  Size: SH

    Note: 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 service sensors will already have the compound applied to the threads. If a sensor is removed from any engine and if for any reason it is to be reinstalled, the threads must have anti-seize compound applied before reinstallation.

  1. Install the oxygen sensor and tighten to 35-44 N·m (26-33 lb ft).
  2. Install the oxygen sensor connector.
  3. Install the exhaust manifold heat shield.
  4. Install the air cleaner/resonator assembly. Refer to Air Cleaner Assembly Replacement.