Chevrolet 1995 Lumina Owner's Manual page 183

2. Then keep turning
the pressure cap,
but now push down
as you turn it.
Remove the
pressure cap.
3. After the engine cools, open the coolant air bleed
valve.
I
3.1L L82 (Code M) Engine
3.1L 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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