2009 Express Automobile Owner's Manual

Radiator Pressure Cap
The radiator pressure cap is located near the center of
the engine compartment. See Engine Compartment
Overview on page 5-14 for more information on location.
Notice: If the pressure cap is not tightly installed,
coolant loss and possible engine damage may occur.
Be sure the cap is properly and tightly secured.
Engine Overheating
If your vehicle has the DURAMAX Diesel engine, see
the DURAMAX Diesel manual for more information.
The vehicle has an indicator to warn of engine
overheating.
You will find an engine coolant temperature gage on
your vehicle’s instrument panel. See Engine Coolant
Temperature Gage on page 3-33 for more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away.
See Roadside Assistance Program on page 7-8.
If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are running.
If the engine is overheating, both fans should be running.
If they are not, do not continue to run the engine and
have the vehicle serviced.
See if the engine cooling fan speed increases when idle
speed is doubled by pushing the accelerator pedal down.
If it does not, your vehicle needs service. Turn off the
engine.
Notice: Engine damage from running the engine
without coolant is not covered by the warranty.
Notice: If the engine catches fire because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.
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