Ther is something wrong with my A/C, sometimes it blows hot air, some times it blows cold air. I don't know what is going on. Please help. Thank you

 

needs a recharge

 

I have ACC but for some reason the air it blows is equally cold anywhere between 65 and 84 and only when I set it at 85 it warms it up. And the freon is not the problem. It's no big deal.. I can live with it, but the heat outside is already calling for ice cold A/C. Any ideas as to how that could be fixed? Thanks

 

Why are you sure the refrigerant is not the problem? From what you describe, I'd guess the a/c is blowing ambient-temperature air at all settings except maximum temperature. That could quite possibly be a problem with the refrigerant charge.

First figure out whether the compressor is operating at all. Get someone to help you and do this: Have your helper sit in the car with the engine running at idle and the a/c system off. You stand at the front of the car, watching the radiator fans and listening. Helper presses the a/c button. You should hear a click, the rad fans should start, and possibly the engine speed might dip slightly. If you don't hear a click then the compressor is not running. If it is not, then either your refrigerant is so low that the low-pressure cutout is prohibiting the compressor, or there is an electrical failure that prevents the compressor clutch from engaging. If the rad fans don't run then you have deep and mysterious electrical problems.

If the compressor is working, check whether the suction line is cold. If it is not, then you have (at least one of) low refrigerant, an internal compressor failure, failure of the metering valve, or a clog inside the system, perhaps in the filter/drier. Maybe somebody else can think of another potential problem. If the suction line is cold, then expect a failure of the climate control module or the little motors that operate the temperature and mode doors, or perhaps most likely, failure of one of the several temperature sensors that the system uses.

 

I would check the temperature resister. If I remember correctly I had a similar problem with my 91 with a blown temperature resister. Mine was located directly behind the glove box, it had two wires coming off of it and two screws that connected it inside the airbox. The part was like $15. This could be your problem, not sure if it is in the same spot but definitely worth a look before you have to take it to the dealer.