GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Important: Use care when handling the engine coolant temperature (ECT) sensor. Damage to the ECT sensor will affect proper operation of the fuel injection system.


    Object Number: 641349  Size: SH
  1. Drain the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.
  2. Disconnect the ECT sensor electrical connector (1) from the ECT sensor (2) located next to the upper radiator hose on the cylinder head.
  3. Remove the ECT sensor (2) from the cylinder head.

Installation Procedure


    Object Number: 641349  Size: SH

    Notice: Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

  1. Install the ECT sensor (2) into cylinder head.
  2. Tighten
    Tighten the ECT sensor to 20 N·m (14 lb ft).

  3. Connect the ECT sensor electrical connector (1).
  4. Refill the engine coolant. Refer to Cooling System Draining and Filling in Engine Cooling.