Still no luck but bad luck...
I found that some other guys have had similar problems on another thread, and found a tutorial on how to bleed/flush the system. So, I tried that yesterday. The car is now idling around 230, but I am seeing white smoke, with water and oil in the exhaust. I don't see any coolant in the exhaust, but from what I've read so far, the white smoke would be an indicator that the coolant is being burned off due to a blown head gasket. The oil pressure has started to decrease as well, but when checked, looks like regular color to me.
Would a blown head gasket also account for oil in the exhaust? It is literally sludging up at the ends of the exhaust tips (I don't think that's normal, but correct me if I'm wrong). Kinda annoyed at how the "professionals" at Midas didn't notice that (unless it just started happening, but I kind of doubt that; then again, the mechanic who I dealt with said something along the lines of "wow that's a big engine"...
).
Sorry for the delay in posts, I have the car in West Paterson, but I'm in Rockaway most of the week, so it's not every day that I can work on it. I do appreciate all the replies though!
More answers to questions:
Yes, the overflow tank is hooked up.
When it overheats, it goes all the way into the red zone.
The fans are kicking on.
It has only overheated while driving, but I have not let it idle from a cold start to check, other than today after the flush.
I do have the airdam on.