Pontiac Repair: 2000 Grand AM GT, coolant loss, coolant leak

Question
I have a V6 automatic Grand AM. I had the "problem" fixed twice at a local dealership and it is occurring again. The car has a coolant problem that consist of loosing coolant, overheating, and loss of heater. The dear had replaced the thermostat and pressure cap.  Any Idea?

Answer
Hi
I would suspect the Lower intake manifold gaskets leaking.
I am suprised...It is VERY common on these engines.
Take it somewheres else.... have it diagnosed PROPERLY.
A coolant pressure test will have eliminated the cap.
The thermostat will not cause a coolant loss.
The coolant pressure test will USUALLYalso pinpoint the location of the coolant leak.
I Hope this helps
Pawl