Hi all,
I went to the dealership, they pulled out a stethyscope and told me that the grinding noise I'm hearing isn't the AC compressor, its my water pump. Ok that's fine, but that still doesn't tell me whats wrong with my AC. Currently, when I turn the dial to "Max AC", the air coming out of the vents is the same temp as the outside air (About 90*F).

The compressor kicks on and off every few seconds. The line gets pretty cold (water condenses on it) but I think it could be colder. This makes me think it's low on freon. (The dealership also told me it was probably low on freon)

So I picked up a gauge and 2 cans 134-A from AutoZone. I hooked up the gauge and the pressure seemed really high. 75psi? The ambient temp was about 90*F. I hooked up a can to the low line just to see of it would take any more and I can't tell if anything went in. The can doesn't seem to weigh any less. Now the AC line along the fender doesn't get nearly as cold. What the @#$% is going on?

I NEED the AC to work tomorrow, I have a 2hr drive with a hot date tomorrow afternoon and its supposed to be in the 90's. PLEASE HELP! I'm freaking out here.

 

Only read pressure when the compressor is running. If that reading WAS while the compressor was running, chances are the system is OVER charged. The compressor kicking on and off though would make you think it was UNDER charged. If the pressures are high like that, and the compressor is still doing its dance, there is probably a blockage in the system somewhere.....

Another thing to look at is the temp door, in the heater box. In my wanderings, it has come to my attention that the little coupler between the actuator for the door, and the little motor that runs it, is a weak point, and tends to fail... (mine does the same thing, A/C system seems great, pressures are good, compressor engages, and stays that way, etc, but, the air is really close to ambient temp......) I am thinking maybe the coupler hasn't failed totally yet, but, also does not move the door fully..... Heat works great. Just what I need on 90* days.

According to popular theory, the little motor is on the bottom of the box, and might even be serviceable without having to rip half of your interior out.... There was a thread about a metal coupler just the other day.

 

75psi was with the compressor running. I don't think it could be over charged because it worked fine last year, and I never added any more refrigerent. So I guess it sounds like there's some blockage somewhere? I'll take a look at the door thingy too, I think I know where that is.

Now the high line doesn't even get cool to the touch with the AC running. When I tried to put more refrigerent in some must have leaked out.

 

if you got a reading of 75 psi on the low side, then you system is way overcharged, but that would be almost impossible to do. the compressor cycling means that it is undercharged. the line freezing up means the comp is working so that is a good sign. i would put vacuum to the system to suck everything out, and start over with a recharge. if that 75 psi is accurate, than you probably have a clogged orifice tube, which is not serviceable. you have to replace the high side line.

 

check the schrader valve pin on the low side side port If it is stuck your autozone gage will reas high presure. It is the presure in the can of freeon and nothing is going in. Push on the valve with a small screwdrive or pair of needle nose pliers and see if you can get it to open. BE CAREFUL as if there is any freeon in the system it will cone out at you.

 

if its in the 90's, your right, you got yourself a hot date ^.^