1999 A8 Intermitent A/C Problem
 

My A/C works fine when not parked in heat. If it is too hot out, I hear gurgling coming from the vents before I start the car. I turn the key to the on position, the gurgling stops. I start the engine, I turn on the A/C, it runs for a little while, then I start hearing a what sound like a bearing or something struck in a fan. I works fine any other time, only when it is hot out. It started last year intermittently. I would usually run fine. Again, only when it is hot outside. I run it in a cool area and I do not hear the gurgling, it works fine. It is always the same, I hear the gurgling first. There is no water on the mats or coming out the vents. The heater works, etc. Are the drains clogged? Does the evaporator need to be flushed or air forced through it? I would appreciate any suggestions.

Normally if AC drains are clogged, they overflow into the carpet or right onto your feet. By the way, they ALWAYS do clog eventually and worth checking/correcting:

http://www.audipages.com/Tech_Articl...tordrains.html

The symptoms you describe don't "sound" like a clogged drain problem...more like a problem in the sealed refrigerant system...low on refrigerant, oil or a component overheating. The systems can be flushed (or at least drained/refilled) and the refrigerant contains a measured amount of lubricating oil (has to be near correct amount), which is the ONLY lubricant the compressor gets.

Thank you for your answer.

I was wondering, is the A/C in any way connected to the vacuum system which controls the door locks? The reason I am asking is, in the trunk lid itself, by the right rear light, there is some sort of valve I know has to be associated with the lock system.

I need tear apart and see, (a little difficult in my current circumstance) but there is a hiss and the pump motor runs a little before it turns itself off, also in the rear. I know it's a leak.

I think is started right around the time my A/C started acting up, so I was just wondering if they are linked in any way.

Again, thank you for your answer, it is very much appreciated.