GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1996 🢒 Blazer - 2WD 🢒 Engine 🢒 Engine Controls - 2.2L 🢒 Heated Oxygen Sensor Replacement

Removal Procedure

Tools Required

J 39194 Oxygen Sensor Wrench

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.

When the engine temperature is below 48°C (120°F), the Heated Oxygen Sensor (HO2S) may be difficult to remove. Excessive force may damage the threads in the exhaust manifold or the exhaust pipe.

  1. Turn OFF the ignition.

    2. Caution: To avoid any vehicle damage, serious personal injury or death when major components are removed from the vehicle and the vehicle is supported by a hoist, support the vehicle with jack stands at the opposite end from which the components are being removed and strap the vehicle to the hoist.

  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the electrical connector.

    4. Object Number: 10975 Size: SH

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

  4. Carefully remove the rear heated oxygen sensor using J 39194 the Oxygen Sensor Wrenchl.

Installation Procedure

Important: A special anti-seize compound is used on the Heated Oxygen Sensor (HO2S) threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor easier to remove. New, or service replacement sensors already have the compound applied to the threads. If the sensor is removed from an engine and if for any reason it is to be reinstalled, the threads must have anti-seize compound applied before the reinstallation.


    Object Number: 10975 Size: SH
  1. Coat the threads of the heated oxygen sensor with anti-seize compound GM P/N 5613695 or the equivalent if necessary.
  2. Install the sensor.

    3. Tighten
    Tighten the sensor to 41 N·m (30 lb ft),

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the HO2S 2 electrical connector.