Chevrolet 1997 Camaro Owner's Manual page 229

How to Add Coolant to the Radiator
(VS Engine Only)
I
NOTICE:
The LT1
Engine (Code
P)
has a specific radiator
fill procedure. Failure to follow this procedure
could cause your engine to overheat and be
severely damaged.
1. You can remove the radiator pressure cap when the
cooling system, including the radiator pressure cap
and upper radiator hose, is no longer hot. Turn
the pressure cap slowly counterclockwise until
it
first stops. (Don't press down while turning the
pressure cap.)
If you hear a hiss, wait for that
to
stop. A hiss means
there is still some pressure left.
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