Engine Overheating - GMC Chevrolet Express 2022 Owner's Manual

176 Vehicle Care
6. Start the engine and let it run until the
upper radiator hose can be felt getting
hot. Watch out for the engine
cooling fan.
7. By this time, the coolant level inside the
radiator filler neck may be lower. If the
level is lower, add more of the proper
mixture through the filler neck until the
level reaches the base of the filler neck.
8. Replace the pressure cap. At any time
during this procedure if coolant begins to
flow out of the filler neck, reinstall the
pressure cap.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.

Engine Overheating

Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
The vehicle has an indicator to warn of
engine overheating.
There is an engine coolant temperature
gauge on the vehicle's instrument cluster.
See Engine Coolant Temperature Gauge 0 72.
If the decision is made not to lift the hood
when this warning appears, but instead get
service help right away.
If the decision is made 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, the
fan should be running. If it is 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, the
vehicle needs service. Turn off the engine.
If Steam is Coming from the Engine
Compartment
Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
Climbs a long hill on a hot day.
Stops after high-speed driving.
Idles for long periods in traffic.
Tows a trailer. See Driving on Grades
under Trailer Towing 0 157.