I noticed my monte carlo started over heating. At first I was out of town and I stopped for a brief second and noticed the over heat. I then started driving and my system cooled back down. Now it over heats and stays over heated. I changed out the t-stat. I've tried changing out my coolant. I did not run it for a long time (close to a year) and decided to revisit the issue. I took my t-stat right out today just to see if it would had any changes.. (of course it didn't). It did however blow lots of white smoke when starting it today
I don't notice any coolant in my oil. My tail pipe is dry. It jumps up and doesn't cool back down until I shut it off. I dont notice any leaks anywhere.. I did start to hear gurgling noises while sitting inside my vehicle last year when this issue first happened. (which may be the issue?). I'm not very mechanically inclined so take it easy on me! :P

 

Maybe a gasket is blown - head or intake manifold?

Lots of white smoke usually means the engine is drinking coolant.

 

sounds like a clogged radiator, do a coolant flush. Also use a IR gun to see the temp of the radiator at various parts. If ti is consistent it flows fine, if there are hot and cold spots it's a clogged radiator. Otherwise my guess is a blown head gasket. The engine should run really cold with no T stat in place when driving, ask me how I know.

also removing the air dam shroud below the radiator, isn't good as it helps to push air into the radiator when driving to keep things cool

 

I have seen this several times. A bad radiator cap won't hold pressure and will allow overheating. It holds it when its cold, but when it gets hot, the spring loses tension.
Pinhole leaks in the radiator hose(especially the lower), can cause slow overheating over time.

 

I have seen this several times. A bad radiator cap won't hold pressure and will allow overheating. It holds it when its cold, but when it gets hot, the spring loses tension.
Pinhole leaks in the radiator hose(especially the lower), can cause slow overheating over time.
Gurgling water in the interior is often a leaking heater core. That can also cause overheating. Good luck.