The cooling system consists of the following components:

The coolant system works to keep the engine at its most efficient operating temperature at all engine speeds and in all driving conditions. The system directs some engine coolant through hoses to the heater core in order to provide defrost and passenger compartment heat. A coolant recovery reservoir connects to the radiator in order to recover engine coolant displaced by expansion. As the engine cools, vacuum draws the engine coolant back into the radiator.

On the 3800 (VIN K) engine, the water pump draws the coolant from the radiator. The coolant circulates through coolant jackets in the cylinder block, and then through coolant jackets in the cylinder heads. The coolant is then directed back to the radiator.

On the 5.7L (VIN P) engine has a reverse flow coolant system. The coolant is drawn from the radiator by the water pump. The coolant is circulated through coolant jackets in the cylinder heads, then through coolant jackets in the engine block. The coolant is then directed back to the radiator.

This sensor controls a temperature gauge in the instrument cluster. The temperature gage indicates the operating temperature of the engine. Refer to Engine Controls for engine coolant temperature gage location and diagnosis.

The engine block coolant drain hole plugs are on either side of the engine block just above the oil pan. Knock sensors are installed in both drain holes. Remove the plugs and the sensors when you completely drain the cooling system.

The engine block coolant drain hole plug is on the left side of the engine block. Remove the plug when you completely drain the cooling system. Also, remove the knock sensor on the right side of the engine block.