Thread: Car runs hot with a/c on

Hey I have an issue I forgot about, and I should try and figure it out. My car during summer starts to overheat when I have the a/c on. If I turn it off, the car will cool down again. What could be the cause of this? My radiator is new, my coolant mix is good.

does the 2nd fan kick on?

Yes the fans work the way they should. The compressor is new.

how many miles on the car??? whens the last time the WP or even the Tstat was changed

New A/C radiator? There is a special A/C radiator in front of my radiator on my B13.

A/C has special coolant like R134a coolant (IRDK what coolant is has) and I'm not sure, but I don't expect it to be hooked up with engine coolant system.

I'm gonna remove it too

I don't think it's the water pump or thermostat. It works perfect, even in 100+ degrees. The only time it will start to overheat is when the a/c is on and the temp outside is close to or above 100 degrees. The engine has about 70k on it. The a/c compressor, evaporator, and r134 are new. The car has a new radiator. The fans come on at the correct times. I just can't figure it out.

Maybe your radiator is getting heat soaked from the a/c condenser?

Sounds like the thermostat isn't opening as far as it should.