GMC 2003 C4C042 Owner's Manual page 100

NOTICE:
If the wait to start light stays on, it means that
your vehicle could have one of several problems,
so you should have it serviced right away.
3. If the engine does not start after 15 seconds of
cranking, turn the ignition key to OFF. Wait
one minute for the starter to cool, then try the
same steps again.
If you're trying to start your engine after you've run
out of fuel, follow the steps in "Running Out of Fuel."
See "Diesel Fuel Requirements and Fuel System" in
the Index.
When your engine is cold, let it run for a few minutes
before you move your vehicle. This lets oil pressure
build up. Your engine will sound louder when it's cold.
NOTICE:
If you're not in an idling vehicle and the engine
overheats, you wouldn't be there to see the
overheated engine condition. This could damage
your vehicle. Don't let your engine run when
you're not in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in
cold weather.
Use the recommended engine oil when the outside
temperature drops below freezing. See "Engine Oil" in
the Index. When the outside temperature drops below
0 _ F ( 18 _ C), use of the engine coolant heater is
-
recommended.
If you experience longer cranking times, notice an
unusual amount of exhaust smoke or are at higher
altitudes (over 7,000 ft. or 2 135 m), you may use your
engine coolant heater. See "Engine Coolant Heater" in
the Index.
See "Diesel Fuel Requirements and Fuel System" in the
Index for information on what fuel to use in cold weather.
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