Pontiac 1998 Firebird Owner's Manual page 229

When the coolant in the coolant recovery tank is at
FULL COLD
start your vehicle.
If the overheat
warning
continues, there's one more
thing you can
try.
You can add the proper coolant
mixture directly to
the
radiator but be sure the cooling
system is cool before you do it.
'
A
CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Don't spill coolant on a hot engine.
F
A
CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap
--
even a little
--
they can come out
at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap
to
cool
if
you ever have
to
turn the pressure cap.
5-20