I just got a 90 S10 and was trying to find out why the AC didnt work. When i first got it, it wasnt blowing at all. I finally got it to blow and it was hot air. I put Freon in it but nothing. still blowing hot air and not sure what to do. The compressor kicks on and everything but not sure about it. The part where the belt is that turns it compressor, in the front, it turns, stops, turns, stops... is it suppose to do that? Please anyone help with my questions?
Yes it is supposed to start and stop that is the clutch for the compressor you may have a clogged up office tube or expansion valve depending on which one you have.
If the compressor is air temp, then I'd check the wires to make sure it has not come undone or broken.Low on charge, you will have to call a Pro in to fix the problem.