I switched to the 180 maybe 2 months ago. It was freezing out then so it stayed cool. It'* warming up and about 40-65 degrees for the last couple weeks and my temp gauge has gotten to 200 and over 200 at times. It cools off eventually but will often go back to 200 or over a bit. WTF is up? I don't even race the engine. There'* no doubt it'* in right and tight, so should I get another new stat or what? Thanks a lot, this is a PITA, but hopefully nothing'* wrong.

Once it opens, and stays open, that stat won't 'cool' your car. It still relies on the air moving through the radiator to remove the heat from the coolant. If you let it idle, it will STILL overheat, it just takes longer. That'* the whole idea....prevent the initial heat saturation from killing your engine. Your only other option is to drill the stat. In your climate, I'd suggest no more than two 1/16" diameter holes.