Chevrolet 2001 Malibu Owner's Manual page 226

1. You can remove the coolant surge tank pressure cap 2. Then keep turning the pressure cap slowly, and
when the cooling system, including the coolant surge remove it.
tank pressure cap and upper radiator hose, is no
longer hot. Turn the pressure cap slowly
counterclockwise (left) about two or two and
-
one half turns. If you hear a hiss, wait for that to
stop. This will allow any pressure still left to be
vented out the discharge hose.
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