Why did my car overheat when I turned on the AC?

Question

HELP!!!! I was stuck in traffic with the AC turned on full blast when my car started overheating. When I got home I heard the coolant boiling really loud. I took my car into the shop the next day to have the mechanic look at it and he told me that the Thermal stat, water pump, radiator and hoses were all working fine and that I also didnt have any leaks or air blockage preventing coolant from flowing through. He said it might be something with the AC or some guage with the AC. Does this sound right? What other things might cause my car to overheat when the ac is on? Thanks

Answer 1

Open the hood, at home, start engine turn on a/c and see if cooling fan comes on. If not that is your problem. Better find a new mechanic. I assume it is new enough to have electric fan ? The fan must come on when a/c turned on.

Answer 2

most likely it was a hot day and you overworked your car.

Answer 3

try look at your auxillary fun if it's working.

Answer 4

"He said it might be something with the AC or some guage with the AC."?  Is that ACTUALLY what he said?  If so, I'd find someone else to look at the car.  Did we check to see if the cooling fan is operating properly?  You don't mention what kind of vehicle this is, but if the fan isn't on then the compressor is running, it's going to overheat.  The A/C won't cool very well BEFORE it overheats, either.

Answer 5

you might have a simple a problem as your radiator or condensor are dirty or plugged up they might just need blown out

Answer 6

It means it was too hot out and your engine does not have enough cooling capacity to run the AC at full blast when the engine is idling. If you are stuck in traffic, turn the AC down or off if the car starts starts to show signs of overheating.

In June I was in Death Valley and it was 119F out. To get out of there, you have to make a 5000 foot climb in less than 20 miles. The car's temperature started to go way up and we had to turn the AC off and turn the heater on full blast for more cooling so the car would not c**p out on us.  

Answer 7

depending on what kind of vehicle you have which would be helpful to know... it sounds like your fan clutch is going out or your electric fan is starting to malfunction.