GTP running rough when hot

[reem98]

My 98 GTP with a reprogrammed ecu from 3800performance.com began running really rough yesterday in the extreme heat. I was caught in a traffic jam and every time I would run my A/C the water temp would slowly climb to about 240 and then the car would begin to shake and idle poorly.
It basically felt like a bad miss. I'd turn off the A/C the water temp would come down and it would idle correctly again. Has anyone ever experienced this before?

 

[BillBoost37]

sounds like your AC compressor is putting more of a load on the motor than it should or your fans aren't functioning 100%. Most likely the AC compressor is causing you some issues.

 

[reem98]

The odd thing is it wouldn't go away when I turned the ac off it would only stop once the temp fell down to say 225 or so

 

[BillBoost37]

There is programmin in place to limp the motor on less cylinders etc when it's too hot.

 

[reem98]

Ok that makes sense cause that's exactly what it felt like

 

[Zef_66]

There is programmin in place to limp the motor on less cylinders etc when it's too hot.

Probably this.

You may want to consider doing a flush of the cooling system. Sounds like you are not cooling to car properly.