GMC T-Series 2007 Owner's Manual page 220

If Steam Is Coming From Your Engine
CAUTION:
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Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from
the vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire.
You or others could be badly burned.
Stop your engine if it overheats, and get
out of the vehicle until the engine is cool.
Notice: If your engine catches fire because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
220
If No Steam Is Coming From Your
Engine
An overheat warning, along with a low coolant light,
can indicate a serious problem. See Low Coolant
Warning Light on page 129 for more information.
If you get an engine overheat warning with no
low coolant light, but see or hear no steam,
the problem may not be too serious. Sometimes
the engine can get a little too hot when you:
•
Climb a long hill on a hot day.
•
Stop after high-speed driving.
•
Idle for long periods in traffic.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. If climbing a hill, downshift to raise engine and
fan speeds.