GM Service Manual Online
For 1990-2009 cars only

Object Number: 2001257  Size: MF

Callout

Component Name

Preliminary Procedure

Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.

1

Heated Oxygen Sensor

Caution: The oxygen sensor uses a permanently attached pigtail and connector. Do not remove the pigtail from the oxygen sensor. Damage to or removal of the pigtail connector could affect proper operation of the oxygen sensor.

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

Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution in the Preface section.

Caution: Refer to Fastener Caution in the Preface section.

Procedure

  1. Disconnect the electrical connector.
  2. Uncrimp the heat shield from the O2 sensor wiring harness.

Tip

    • The in-line connector and louvered end must be kept clear of grease, dirt or other contaminants. Avoid using cleaning solvents of any type. DO NOT drop or roughly handle the heated oxygen sensor (HO2S).
    • The HO2S may be difficult to remove when the engine temperature is less than 48°C (120°F).
    • A special anti-seize compound is used on the HO2S threads. The 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 have the compound applied to the threads. If a sensor is removed and is to be reinstalled, the threads must have an anti-seize compound applied before installation.

Tighten
42 N·m (31 lb ft)

Special Tools

J 39194 Oxygen Sensor Wrench