Tools Required

J 45861 ECT Sensor Socket

1. Partially drain the cooling system to a level below the engine coolant temperature (ECT) sensor. Refer to Cooling System Draining and Filling .
2. Disconnect the engine wiring harness electrical connector (1) from the ECT sensor electrical connector.
3. Remove the ECT sensor electrical connector from the camshaft cover.

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

4. Using the J 45861 (2) carefully remove the ECT sensor (3) from the cylinder head.

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

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. If installing the original sensor or a NEW sensor without sealant, apply thread sealer GM P/N 12346004 (Canadian P/N 10953480) or equivalent.
2. Thread the ECT sensor into the cylinder head by hand.

Notice: Refer to Component Fastener Tightening Notice in the Preface section.

3. Using the J 45861 (2) tighten the ECT sensor (3).

Tighten
Tighten the sensor to 14 N·m (10 lb ft).

4. Install the ECT sensor electrical connector to the camshaft cover.
5. Connect the engine wiring harness electrical connector (1) to the ECT sensor electrical connector.
6. Refill the cooling system. Refer to Cooling System Draining and Filling .