Air Conditioning Leak in dash

[Island_Tom]

Greetings!

Last Summer I found my A/C was not working on my '03 Vue. There was also an occasional hissing in the dash when the fan was on, heat or A/C. After having my A/C recharged, I found it was not working again after a few days. My local repair shop said there was a leak behind the dash somewhere and estimated the repair to be around $1200, mostly labor for the complexity of the dash. I trust this repair shop very much, but I was wondering if this is just scaring the shop. Has anyone had a similar issue? Every other tech issue I have had with this car, I have found on the forums, not this one though.

Thanks!

Tom

[fdryer]

Well, very few forums will give you specific answers when it comes to a/c problems since its a whole separate system altogether. You might be able to narrow down the problem if you're willing to do some basic troubleshooting; http://www.saturnfans.com/forums/showthread.php?t=80107. A leak can be anywhere and not likely in the dash but it can happen. The refill last year may have just been enough to run until the refrigerant leaked out. If you still have the same problem from last year, its still the same leak. The trick is to spend the time (not very much but more if you want to attempt saving money to do as much for yourself before paying the expensive way) finding the leak.

[VTchemist]

If the shop checked for leaks (and found none in the compressor, dryer or hoses), they may think it could be the heat exchanger (under the dash). It's a bit of labor to get in there.

The hissing sound under the dash is not an indication of a leak. Insufficient freon pressure will cause the liquid freon to flash evaporate in the heat exchanger. Low pressure is from a leak could be from anywhere. The hissing noise is just the confirmation your freon is low.

If the shop has made its conclusion on the "hissing sound", they have not really done a good job. Get a second opinion.

My AC went out last summer too. I had a crack in the dryer housing. The dye my shop put in the system when they recharged it helped them track down the leak.

[Island_Tom]

Thanks folks. The shop had put in some kind of dye to find a leak and it was not in the Comp/hoses/dryer. I am the one who noticed the hissing sound. It is probably the exchanger. Any idea how much it would cost to replace parts and labor? Should this be done by a Saturn tech?

Tom

[fdryer]

If in fact that the 'exchanger', as you describe it, is leaking (we describe it as the evaporator coil within the dash console) this will be a labor intensive removal/replacement job requiring disassembling many things inside the car. Its a toss up whether a local repair shop can do the same work that Saturn is supposed to be able to do more efficiently from repair manuals. Have you tried or are interested in confirming that the leak is from the interior of the car and not anywhere else including the firewall connections where the two a/c lines enter/exit? Dye can be seen with the naked eye if searching for it carefully and may be better illuminated with those store bought battery operated UV lights that should illuminate the dye in a garage or shaded area. With some more information, you may be in a better position to determine how to proceed. At least you can verify what you've been told.

[1saxman]

Tom; Take it to a specialty AC shop in your area. They will find the leak, then you can decide whether to let them fix it or Saturn. Like Dryer says, the so-called 'hissing' probably has nothing to do with your problem. VUEs with properly-charged systems still 'hiss'. They all do, really, but in most cars you can't hear it. There's a small orifice at the evaporator, which is under suction (low pressure side of system). When the hot, liquid refrigerant is forced through the orifice, it 'flashes' into a cold vapor and is sucked back into the compressor to be made a hot liquid again. The refrigerant coming through the orifice is the 'hiss' you hear when your system is charged up and running. You will never hear a refrigerant leak unless a hose bursts, then it will only do it once for a few seconds and the low-pressure switch in the compressor will cut it off to prevent damage.