Air Conditioning help!!!!

[ajarocki]

Alright guys it's getting hot in Atlanta already and I know my way around AC systems but I'm completely stumped right now.
The fan control is working no issues there. Fuse for the AC is also good. Clutch engages as long as there is some freon in the pipes.
I vacuumed the lines and only got about 10 lbs mercury with isn't anywhere close to perfect.
So I know I have a leak somewhere. I added freon to the system. 1 can just to see. Had cold air for maybe a day.
Earlier I added UV dye to the system and ran it for close to an hour and checked for leaks.
I have not found any dye in the engine compartment.
Vented the remainder of the dye and freon out of the high side and alot of the dye came back out.
My current guess is the expansion valve is plugged and needs replacement, but would that cause me to have a leak?

Any help is appreciated, I spent some time looking through threads to see if there was an answer to my problem.
Thanks guys
~Alex

 

[The_big_dill]

Both proteges that I have worked on have mysterious leaks in the A/C system... One holds it for a couple weeks, one holds for less than a day.

Although when working on the car and removing a bunch of stuff, I hit one of the lines going to the receiver/drier very slightly and started hearing some hissing. I didn't hit it very hard, but at the length of those pipes, I would imagine it was enough torque to brake the seal.

 

[MrGiggles]

You really need to scrutinize every detail of the A/C system. I've seen some leaks that evacuated the whole system but didn't leave a bit of residue. The condenser and dryer connections need to be checked as well.

If you can get really dry compressed air (like what car painters use) you can pressurize the system with it, and spray everything down with soapy water. Even "dry" compressed is comparatively full of moisture, so this is a last resort.