if we turn the air conditioning off, the car cools back down, but if the air conditioning is on and we idle even for a few moments the car overheats terribly. we live in arizona so this is not acceptable. rented a toyota corolla and did not behave this way, what needs fixed?
my car overheats when idling but only when the air is on. on 1999 Toyota Corolla
I would suspect an issue with the electric cooling fans - you didn't mention if the air conditioning also stops blowing cold air at idle? If the air is staying cold and the engine is running fine but the gauge is showing hot but not truly overheating, its possible you have a wiring issue with the gauge.
when the car overheats the air still blows but not cold, it blows hot
You need to go back to the Basics - If there is no air flow pasted the radiator and condenser (like a faulty electric cooling fan motor) the air conditioning system cannot work properly and that is why the vent temp blows hot - some vehicles have 2 cooling fans - I would start with the cooling fans first, it truly sounds like an air flow problem. Once the issue has been fixed I would suggest having the air conditioning system service, many times when the system has been under a strain (such as your idle time, blowing hot) the system will bleed off freon and then the oil inside the system will not be carried correctly when the system is on, a simple service should prevent future compressor failure if permanent damage has not already occurred.
Hac19 is right on the money,,those cooling fans absolutely should be on when you turn the ac on....One thing to check first that happened to me was to check the fuses!! they are mostly in the engine for the AC...in my car they are. I had ONE fan on and the other not and car got hot! there usually is a little fuse ,,, one for each fan and a relay one for each too. good luck--mackieman always says "start with the obvious and simple and then work your way up" good luck