GMC 1994 Yukon Owner's Manual page 75

lf Your Diesel Engine Won't Start
If you've run out of fuel, look at "Running Out of Fuel" (see "Diesel Fuel
Requirements and Fuel System" in the Index).
If you're not out of fuel, and your engine won't start, do this:
Turn your ignition key to RUN. Make sure that the "GLOW PLUGS" light
is out. Then turn the ignition key to START.
If the light doesn't go off, wait a few seconds, then try starting your engine
again. And, see your dealer as soon as you can for a starting system check.
If the light comes on and then goes off and you know your batteries are
charged, but your engine still won't start, your vehicle needs service.
If the light does not come on when the engine is cold, your vehicle needs
service.
If your batteries don't have enough charge to start your engine, see
"Battery" in the Index.
Be sure you have the right oil for your engine, and that you've changed the
oil at the proper times. If you use the wrong oil, your engine may be harder
to start.
If the engine starts, runs a short time, then stops, your vehicle needs service.
Engine Coolant Heater (Engine Block Heater)
4
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