Chevrolet 2003 Impala Owner's Manual page 283

If Steam Is Coming From Your Engine
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
CAUTION: (Continued)
dov
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.
See "Overheated Engine Protection Operating
Mode" in the Index for information on driving
to a safe place in an emergency.
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. See "Overheated
Engine Protection Operating Mode" in the Index for
information on driving to a safe place in an
emergency.
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