GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Disconnect the negative battery cable.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Drain the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  4. Lower the vehicle.

  5. Object Number: 50967  Size: SH
  6. Disconnect the electrical connector from the ECT sensor.
  7. Remove the #1 spark plug wire from the spark plug.

  8. Object Number: 50974  Size: SH

    Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

  9. Remove the ECT sensor.

Installation Procedure

    Notice: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

  1. Coat the Engine Coolant Temperature (ECT) sensor threads with sealer P/N 12346004 or the equivalent.

  2. Object Number: 50974  Size: SH
  3. Install the ECT sensor.
  4. 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.

    Tighten
    Tighten the ECT sensor to 23 N·m (17 lb ft).

  5. Install the #1 spark plug wire onto the spark plug.

  6. Object Number: 50967  Size: SH
  7. Connect the ECT sensor electrical connector.
  8. Refill the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  9. Start the engine and inspect for leaks.
  10. Inspect the engine coolant level. Refer to Cooling System Draining and Filling in Engine Cooling.