Coolant Temperature Sensor/Switch (For Computer): Service and Repair

Engine Coolant Temperature Sensor Replacement

Removal Procedure

Important: Care must be taken when handling engine coolant temperature sensor. Damage to the engine coolant temperature sensor will effect proper operation of the fuel injection system.






1. Drain the cooling system to a level below the engine coolant temperature (ECT) sensor. Refer to Cooling System Draining and Filling (Static Fill) (Service and Repair)Cooling System Draining and Filling (Vac-N-Fill) (Service and Repair).
2. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement (Service and Repair).
3. Disconnect the engine harness electrical connector (2) from the ECT sensor.




4. Remove the ECT sensor.


Installation Procedure

Important: Care must be taken when handling engine coolant temperature sensor. Damage to the engine coolant temperature sensor will effect proper operation of the fuel injection system.







Important: Replacement components must be the correct part number for the application. Components requiring the use of 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 effect the final torque, which may affect the operation of the component. Use the correct torque specifications when installing components in order to avoid damage.


1. Coat the threads of the sensor with sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent.

Notice: Refer to Fastener Notice (Fastener Notice).

2. Install the ECT sensor.

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




3. Connect the engine harness electrical connector (2) to the ECT sensor.
4. Refill the cooling system. Refer to Cooling System Draining and Filling (Static Fill) (Service and Repair)Cooling System Draining and Filling (Vac-N-Fill) (Service and Repair).
5. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement (Service and Repair).