I am new at this posting and was wondering if someone could give me advice step by step on changing thermostat in pontiac grand prix 2000 3.8 SE,diagrams,pictures etc…all help appreciated,thx
Here’s The Info For Your 3.8L and other Pontiac GP engines.
Purging air from the system after you fill it is important. There should be a bleeder screw on top of the themostat housing for this purpose. Open the bleeder by loosening it. While filling the system with the proper coolant mix, squeeze the upper radiator hose to untrap any air and fill until coolant comes out of the bleeder screw and then close it.
This link should help.
It would behoove you to purchase a Service Manual that is specific to this vehicle.
If you’re going to do maintenance and/or repair it really helps to have a service manual. Haynes manuals are pretty good for most things, but a factory manual is best if you really want detail on everything.
If you can’t find a manual locally, try Books4Cars.com.