Chevrolet MONTE CARLO 1998 Manual page 203

3. After the engine cools, open the coolant air bleed
valve or valves.
3800 V6 (VIN Code K):
There is one bleed valve.
It is located on the
themostat housing.
3 100 V6 (VIN Code M): There are two bleed valves.
One is located on the thermostat housing. The other is
located on the thermostat bypass tube.
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