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

1. Remove the air cleaner. Refer to Air Cleaner Replacement .
2. Remove the front engine oil fill tube. Refer to Oil Filler Tube Replacement for the 6.6L (LLY) engine.



3. Drain the coolant to a level below the engine coolant temperature (ECT) sensor. Refer to Cooling System Draining and Filling .
4. Disconnect the ECT sensor electrical connector.



5. Remove the ECT sensor (1).

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

Notice: Refer to Fastener Notice in the Preface section.




1. If installing the old sensor, coat the threads with sealant GM P/N 12346004 (Canadian P/N 10953480), or equivalent.
2. Install the ECT sensor (1).

Tighten
Tighten the sensor to 20 N·m (15 lb ft).




3. Connect the ECT sensor electrical connector.
4. Install the front engine oil fill tube. Refer to Oil Filler Tube Replacement for the 6.6L (LLY) engine.
5. Fill the cooling system, if necessary. Refer to Cooling System Draining and Filling .
6. Install the air cleaner. Refer to Air Cleaner Replacement .