I'm about to get into an issue that my daughter has with her Cavalier, tomorrow when she comes over.
She said that it has a code indicating cyl one missfire and the coil was changed. Then the car ran well for a couple of weeks BUT was overheating a little. When the the car was running rough, it wasn't overheating, according to her.

I'm going to check the distributer and Cap and rotor, first, tomorrow. I just wanted to see if anyone had ever heard of such an overheating problem.

I'll post again, once I get into this car, tomorrow.

 

Here is some additional information.
The car has 159k miles on it. It's a manual trans. My daughter couldn't wait for Dad to go with her and was dying to go into debt! So she went to a buy-here-pay-her lot and they saw her coming.
Within a week of taking delivery, the engine died and they immediately replaced it with a used engine that who knows how many miles it had on it.
I can't pay for the mistakes she has made but, I have to try to get her back on the road.
I'll post codes, if I can't figure things out, tomorrow.