AveMech1

I took my '98 A6 into an independent shop to get my A/C recharged because it wasn't cooling and a 45 min job has turned into a 2(going on 3) day job. The mechanic says that he checked the system for proper operation and everything seems to be working without problems and can't find any leaks. When he went to charge the system he said he could only get a few ounces into the system before it wouldn't charge any more. He's looked over the lines and major system components for blockage but hasn't found any. Has anyone had a similar experience? I feel pretty confidant in this mechanic's work because he used to come to the airport where i worked and charge up aircraft A/C's. Any thoughts would be appreciated.

Audi Logic

be careful that you don't over charge the system....
its possible that the flaps that channel the air are not working..

AveMech1

How would one go about finding out if they are not working?

rmccomiskie

He should be if he's read the specs. It makes a difference in the way you try to fill the system.

Audi Logic

you need a vag-com or similar cable to log into the climate control system..
if he said all is working then cold air should be going somewhere.. did the lines get cold while testing?
if he charged till it would not take any more freon then the system is over charged.. have him vacuum it out and charge with the right amount of freon and oil then try and figure out the problem..

the system will shut down if the pressure is too high or too low

A6Gary

Unless you have an Avant, you should post over on the C5 ('98 - '04 A6) forum.

AveMech1

Yes, it is an Avant

austinado16

With a set of A/C guages hooked up to the system, this guy would be able to "see" what the suction side of the system was doing, and what the discharge side is doing. That would tell him automatically if the compressor was working, and if there were any blockages. Pretty simple......If you've got "high" low side (suction side) pressure, you know the pump either isn't pumping, or the system is low on freon...or the expansion valve is stuck wide open. If you've got too high of high side (discharge side) pressure, you know the system is either over charged, their's a blockage somewhere, like the expansion valve screen or the exp. valve is stuck closed, or you're not getting good heat transfer through the condensor due to radiator fans not working, or the condensor is blocked, etc.

Our cars run full tempurature hot water through the heater core at all times, and then control the tempurature inside the car by using a blend flap in order to control how much air flows through the heater core....from none, to 100%. The heater core is capable of overpowering the cold of the a/c, so if the blend flap is stuck open and allowing air through the heater core, you'll never get cold air.....Although you would have a compressor running, and sweating metal lines at the receiver/dryer.

Needless to say, either investigate this further yourself, or get the car to a better shop.