99 chevrolet cavalier 2.2 engine,its running hot only when I run the Air Conditioning

Question

I already changed the thermostat,water pump, and radiator

also the cooling fan is straight wired to the relay and i turn it on manually when in demand but it will still run hot if the AC is used

Answer 1

Is the fan turning the right way? If the wires are reversed it will run but will turn the other way blowing air to the front.  Is the spring in the lower radiator hose and have you made sure it is not rusted out.  Can you fit an extra fan or a larger aftermarket fan in the space provided.  All these things might help.  Another question is are you sure it is running hot, not just a faulty gauge.  All cars run hotter when the A/C is on but maybe your gauge decides to peg at that level.  Good Luck as these problems are real hard to solve.

Answer 2

did u remove the radiator and clean it out also .   it could b stopped up from bugs and trash  

Answer 3

did you out a gauge on it? sound like the radiator isn't up to snuff, could be  ok when no AC, but when the air thru the condenser picks up heat the radiator cannot remove enough to cool down the engine.

Answer 4

Did you put the proper rubber ring gasket around  the thermostat base when you changed it. I did a thermostat on my '99 Sunfire and put on the wrong sized ring gasket which allowed coolant to flow around the thermostat instead of through it. This allowed the coolant to go through the rad so fast that it did not have time to cool. And in the winter the coolant was going through the rad when it shouldn't and I d**n near froze because I could not get any heat. I called this car every name imaginable until I discovered my mistake.