When no steam is coming from the engine compartment, lift the hood to check the cooling system. The cooling system components are:

1. Coolant Recovery Tank

2. Electric Engine Cooling Fan

3. Radiator Pressure Cap

Caution: An electric engine cooling fan under the hood can start up even when the engine is not running and can cause injury. Keep hands, clothing, and tools away from any underhood electric fan.

If the coolant inside the coolant recovery tank is boiling, do not do anything else until it cools down. The vehicle should be parked on a level surface.

When the engine is cold, the coolant level should be at or above the FULL COLD mark on the coolant recovery tank.

If it is not, there may be a leak at the pressure cap or in the radiator hoses, heater hoses, radiator, water pump, or somewhere else in the cooling system.

Caution: Heater and radiator hoses, and other engine parts, can be very hot. Do not touch them. If you do, you can be burned.

If there seems to be no leak with the engine on, check to see if the electric engine cooling fans are running. If the engine is overheating, both fans should be running. If they are not, the vehicle needs service.

Notice: Engine damage from running your engine without coolant is not covered by your warranty. See "Overheated Engine Protection Operating Mode" in the Index for information on driving to a safe place in an emergency.

Notice: Using coolant other than DEX-COOL® can cause premature engine, heater core, or radiator corrosion. In addition, the engine coolant could require changing sooner, at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Any repairs would not be covered by the vehicle warranty. Always use DEX-COOL® (silicate-free) coolant in the vehicle.

Caution: Adding only plain water to the cooling system can be dangerous. Plain water, or some other liquid such as alcohol, can boil before the proper coolant mixture will. The vehicle's coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, the engine could get too hot but you would not get the overheat warning. The engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant.

If a problem has not yet been found, but the coolant level is not at the FULL COLD mark, add a 50/50 mixture of clean, drinkable water and DEX-COOL® engine coolant at the coolant recovery tank. See Engine Coolant for more information.

Notice: In cold weather, water can freeze and crack the engine, radiator, heater core and other parts. Use the recommended coolant and the proper coolant mixture.

Caution: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine.

When the coolant level in the coolant recovery tank is at the FULL COLD mark, start the vehicle.

If the overheat warning continues, there is one more thing that can be tried. Add the proper coolant mixture directly to the radiator, but be sure the system is cool before this is done.

Caution: Steam and scalding liquids from a hot cooling system can blow out and burn you badly. They are under pressure, and if you turn the surge tank pressure cap -- even a little -- they can come out at high speed. Never turn the cap when the cooling system, including the surge tank pressure cap, is hot. Wait for the cooling system and surge tank pressure cap to cool if you ever have to turn the pressure cap.

Notice: Your engine has a specific radiator fill procedure. Failure to follow this procedure could cause your engine to overheat and be severely damaged.

The radiator pressure cap is located on the passenger's side of the vehicle in the front of the engine compartment, near the battery and the diagonal cross brace. See Engine Compartment Overview for more information on location.

The radiator pressure cap can be removed when the cooling system, including the radiator pressure cap and upper radiator hose, is no longer hot.

1. Turn the pressure cap slowly counterclockwise until it first stops. Do not press down while turning the pressure cap.

If a hiss is heard, wait for that to stop. A hiss means there is still some pressure left.

2. Then keep turning the pressure cap, but now push down as it is turned. Remove the pressure cap.

Caution: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine.

3. If the vehicle has the 3800 V6 engine, remove the Series  III V6 engine cover shield to access the bleed valve.

3800 Engine





3.1.	Clean the area around the engine oil fill tube and cap before removing. Twist the oil fill tube, with cap attached, counterclockwise and remove it.

3800 Supercharged Engine





3.2.	Lift the engine cover shield at the front, slide the catch tab out of the engine bracket and remove the cover shield.

3.3.	Put the oil fill tube, with cap attached, in the valve cover oil fill hole until ready to replace the cover shield.

Thermostat Housing





After the engine cools, open the coolant air bleed valve located on the thermostat housing near the heater hose.




4. Fill the radiator with the proper DEX-COOL® coolant mixture, up to the base of the filler neck. See Engine Coolant for more information about the proper coolant mixture.

If a stream of coolant is seen coming from an air bleed valve, close the valve. Otherwise, close the valve after the radiator is filled.

5. Rinse or wipe any spilled coolant from the engine and the compartment.
6. Replace the 3800 Series III V6 engine cover shield.

7.1.	Remove the oil fill tube, with cap attached, from the valve cover.

7.2.	Insert the catch tab on the cover shield under the bracket on the engine.

7.3.	Place the hole in the cover shield over the hole in the valve cover. Install oil fill tube and cap by twisting clockwise.

Then fill the coolant recovery tank to the FULL COLD mark.




7. Put the cap back on the coolant recovery tank, but leave the radiator pressure cap off.



8. Start the engine and let it run until you can feel the upper radiator hose getting hot. Watch out for the engine cooling fans.
9. By this time, the coolant level inside the radiator filler neck may be lower. If the level is lower, add more of the proper DEX-COOL® coolant mixture through the filler neck until the level reaches the base of the filler neck.
10. Then replace the radiator pressure cap. At any time during this procedure if coolant begins to flow out of the filler neck, reinstall the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
11. Check the coolant in the recovery tank. The level in the coolant recovery tank should be at the HOT mark when the engine is hot or at the FULL COLD mark when the engine is cold.