Pontiac 1993 Grand Am Owner's Manual page 184

NOTICE
A
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.
1. You can remove the coolant surge
tank
pressure cap when the cooling
system, including the coolant surge
tank
pressure cap and upper radiator
hose, is no longer hot. Turn the
pressure cap slowly about ?A
turn
to
the left and then stop.
If you hear a hiss, wait for that to stop.
A hiss means there is still some pressure
left.
1 8 3
.