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

Engine Coolant Temperature Sensor Replacement

Removal Procedure

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




1. Drain the cooling system. Refer to Cooling System Draining and Filling (9C1, 9C3 Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD, 9C1, 9C3, GE47716 Fill) (Service and Repair).
2. Remove the intake manifold cover, if necessary. Refer to Intake Manifold Cover Replacement (Service and Repair).
3. Remove the exhaust crossover pipe. Refer to Exhaust Crossover Pipe Replacement (LS4) (Service and Repair)Exhaust Crossover Pipe Replacement (LZE/LZ4/LZ8) (Service and Repair).
4. Disconnect the engine coolant temperature (ECT) sensor electrical connector.
5. Remove the ECT sensor.

Installation Procedure

Caution: 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. Coat the threads of the ECT sensor with sealer GM P/N 13246004 (Canadian P/N 10953480) or equivalent.

Caution: Refer to Fastener Caution (Fastener Caution).

2. Install the ECT sensor.

Tighten the ECT sensor to 20 Nm (15 lb ft).

3. Connect the ECT electrical connector.
4. Install the exhaust crossover pipe. Refer to Exhaust Crossover Pipe Replacement (LS4) (Service and Repair)Exhaust Crossover Pipe Replacement (LZE/LZ4/LZ8) (Service and Repair).
5. Install the intake manifold cover, if necessary. Refer to Intake Manifold Cover Replacement (Service and Repair).
6. Fill the cooling system. Refer to Cooling System Draining and Filling (9C1, 9C3 Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD Static Fill) (Service and Repair)Cooling System Draining and Filling (LZE, LZ4, LGD, 9C1, 9C3, GE47716 Fill) (Service and Repair).