GMC 2007 Envoy Denali Owner's Manual page 409

If Steam Is Coming From Your Engine
CAUTION:
{
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.
CAUTION: (Continued)
CAUTION: (Continued)
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.
409