Of course the high pressure and low pressure side have different size fittings, so you can't screw it up.

 

Ok, after some more investigation it looks like the clutch on the compressor is just not engaging. Next question, what would cause that to happen and how much am I looking at to get it fixed?

 

First, check all your connections and electrical lines going to the compressor and make sure they arent loose or damaged. Next check your fuses. Could also be a problem with the switch in the dash. You might want to go to auto zone and get a manual for your car, the wiring diagram will help. I havent had any problems with my mustang, but my trans am did the same thing as yours and it was a relay that went bad.

I cant help you on the price to get it fixed, It took me about 2 hours and a $2 relay for mine.

 

So many people overlook this.... just check the fuse. There's a fuse for the A/C compressor clutch inside the car... It's a 15amp fuse. I expected it to be in the engine bay, but it's not... just one of the mini-fuses inside.

I had mine blow (and it still does when I push the rear defroster button [:@]). You should check that first.

 

Mine was also doin that, blowing but no cold air and it was making a clicking sound. Turned out it was the compressor so they replaced that and the cooling fan in front of the radiator.

 

I did think to check that, but I must admit it took me a little while to think about a fuse problem. Unfortunately it was not the fuse. I will just have to take it to the shop tomorrow I suppose.

 

Follow the suction line back toward the firewall. There should be a pressure switch in the line. Unplug it, bend a paper clip into a u shape, and stick it in the plug. If the clutch then engages there is your problem. I would still check the pressure, as the clutch won't engage with a low pressure in the system.