I've been having a bit of a problem with my ac in my yj wrangler it blows cold when it wants to and then at times it will stop blowing cold air and blow hot air. Only way I can get it back to cold it to turn it off for a bit then keep turning it on and pray it comes out cold but by then I'm already drenched in sweat. Is there something I can do to fix this? I believe it has antifreeze? Is it because its so old? Do I need to change the compressor? Maybe a hose or something is broken? What can I do
My guess would be the compressor clutch is going bad, but as stated above being to low or to high on refrigerant will cause the system to not function proper. One thing you could try is when the ac is not working correctly unplug the wire connector that is on top of your receiver dryer and use a jumper wire and see if the clutch kicks in. If it doesn't then that will tell you your clutch is bad.
My 90 had a similar problem. I cleaned the contacts on the ac relay, and the plug on the compressor. It helped, they had a lot of corrosion built up. But now it intermittently happening again. But now if I turn it off then right back on it blows cold. I think my problem might be the power switch it the temp knob