Chevrolet 2003 Monte Carlo Owner's Manual page 275

10. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.
11. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL@ coolant mixture
through the filler neck until the level reaches
the base of the filler neck.
12. Then replace the pressure cap. At any time during
this procedure if coolant begins to flow out of the
filler neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up like this.
13. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the HOT
mark when the engine is hot or at the COLD mark
when the engine is cold.
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