Pontiac 1999 Grand Am Owner's Manual page 208

3. Then fill the coolant surge tank with the proper
mixture, to the FULL COLD mark or just above the
small cylinder at the base of the opening.
5-16
4. With the coolant surge tank pressure cap off, start the
engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches the FULL COLD mark, or just
above the small cylinder at the base of the opening.
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