Cadillac 1994 Eldorado Owners Literature page 238

k
1.
(Don't press down while turning the pressure cap.)
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 to the
left until it first
stops.
If you hear a hiss, wait for that to stop. A hiss means there is still some
pressure left.
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