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.

  1. Disconnect the oxygen sensor electrical connector.

  2. Object Number: 1394064  Size: SH

    Notice: The use of excessive force may damage the threads in the exhaust manifold/pipe.

    Important: If the engine temperature is not above 48°C (120°F), the oxygen sensor may be difficult to remove.

  3. Remove the heated oxygen sensor (HO2S).

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1394064  Size: SH

    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.

  1. Install the HO2S.
  2. Tighten
    Tighten the HO2S 1 to 42 N·m (31 lb ft).

  3. Connect the oxygen sensor electrical connector.