Originally Posted by kakashi169
ac blows warm air out...went to RMP and refilled it with freon...still warm air
i suspect a leak some where??
1) Once RMP "topped up" the refrigerant, did the cold air start to come out from the vents?
2) If 1) is yes, and now hot air is blowing again then any leak big enough to empty the charge in a 24 hour period is typically visible/audible right away. You most likely have a hole in a condenser or one of the o-rings is busted. The best way would be to empty the system and pressure test it to figure out where the leak is.
3) If 1) is no then you probably have a different issue at hand. The first thing would be to hook up the gauges and see what the low/high pressures are. Assuming that low pressure is ok, you may have an issue with the pressure switch or the compressor clutch. If low pressure is low then it's back to step 2).
See if you can tell if the compressor kicks in when you turn A/C on. It is usually quite simple to see as the RPM might dip and you will hear the A/C clutch and relay engage as you press the A/C button. Also the electric fan should start around the same time. If the compressor starts working but the hot air still blowing from the vents, it is possible that the expansion valve is gone.
Ultimately, at this point in time you are probably better off taking the car to an A/C specialized shop who would be able to properly diagnose the problem.
The FSU (First Stage Unit aka Blower resistor) has nothing to do with your A/C. To my knowledge the outside temp sensor also has no effect on the operation of the A/C unit - the pressure switch is typically the only component that determines if the compressor is safe to run.