needmorespeed

I don't know where to begin. At one point in my infinite wisdom, my ac didn't seem to be blowing as cold as it should be. I added some R134a. AC stopped working. Drove a couple years with the windows down. Now this summer I have been trying to figure it out.

I added some R134a with some dye. I didn't see anything. Nothing by the condensor, compressor, the lines, the fittings, the drier. No green glow.

So I think it must be the evaporator. I pull the dash and get to the heater box. Fun fact, the evaporator doesn't come out of the heater box. I can see absolutely zero dye anywhere in the heater box from the evaporator. At the same time I replaced the drier, since it had been exposed to the atmosphere for a couple years.

Since I can't see any leaks, I button everything back up. I go down to the shop and have them try and figure it out. They evac and recharge the system. Works for a couple days, then I take the car to the dealership to fix the electrical issue from pulling the dash (apparently my car had an aftermarket alarm system that was never fully removed when I bought it from a different dealership).

Now the car sits with no AC, right back at square one but with a newer drier, which may not be effective after being exposed to the atmosphere for a couple weeks now.

I know the compressor stills kicks on from the few days it worked. The condensor have 115K of the **** kicked out of it from road debris. The fins are flattened in quite a large area. I don't want to start throwing parts at it.

Any thoughts? Ideas? I have a manifold gauge set that I am going to hook up this weekend if I can find a vacuum pump.

dawson1112

If the compressor is is kicking on normally when you turn the A/C on then the system is charged. The hi/lo pressure switch is would not let the compressor engage if the system pressure was to hi or low.

I suggest looking into weather or not the blend door is operating correctly. Look in the glove box, behind that is a vacuum reservoir that has some vacuum lines plugged into it. You have to drop the glove box down all the way to get to it. Sometimes those lines or one of them come off and you loose vacuum to the controls. I had the same problem with my 2000.

jwog666

are you checking for the dye with a black light? alot of the time you will not see the dye without a uv light to make it glow. it has to be leaking from somewhere, if u cant see the dye you may have to use a electronic leak detector, they are very sensitive and will find leaks that are very small

Camster

I agree with 666.
I don't know if I'm right or wrong about this,but I'm usually inclined to think that there is a compressor leak.

dawson1112

IF there was a leak and the system was so low that it wont blow cold air then the hi/low switch would not kick the compressor on. If the compressor is kicking on then its got to be something else.

Usually the first sign of a leak is the compressor kicks on and off repeatedly. Then it will not kick on at all due to low line pressure.

needmorespeed

The compressor only kicks on when I get it recharged or add some R134a. After it sits for awhile, it no longer kicks on.

I had the dash apart to check the evaporator for a leak. The vacuum lines looked fine. They are hooked up and my heat works correctly. I can adjust the heat up and down. So I would think since I have vacuum control for heat I would for AC as well.

needmorespeed

I went to the auto parts stores, got the R134a with the dye and bought the glasses and flashlight leak detector kit.

I think I may have try an electronic leak detector that camster suggested. I am going to try and find a place that rents AC vacuums. I borrowed a hi/lo AC pressure gauge set (manifold?) to check the vacuum on the hi and lo sides. Hopefully I can pull enough of a vacuum and see which side loses the vacuum to try and help narrow it down.

Is it worth it to replace the condensor? It is pretty beat up and AM has them for around 100 bucks. How difficult is it? It doesn't look like there is much room on the edges to get to the connection points on the lines to separate the condensor from the lines.

jwog666

im my experience you will virtually never find a leak by pulling a vacuum,think of it like this atmospheric pressure is 14.7psiA, so in a perfect vacuum all you have is 14 psi trying to get in, compare that to 30-200psi of a charged operating system trying to escape. also the 2 sides of the system arent seperate from 1 another, so you cant just pull a vacuum on 1 side or the other, you will be pulling a vacuum on the whole system at once. if the system was open to atmosphere, and you just added r134 without first pulling a vacuum you will have problems regardless, there can be no air in the system for correct operation. since the leak tester is quite expensive, i would maybe find another shop to look at it, and have them find and show you the leak/s before you repair them, and make sure that they back their repair, not just do a charge and send it out the door. good luck