Eddie266

is there any common issues with the 06 a4 that could make the a/c stop blowing cold? The car blows cold during the night but during the day it gets really hot and the a/c stops blowing cold i live in las vegas and its really hot during the day but in the nights its like 60 degrees Fahrenheit. I tried to add r134 but the gauge said it was already overfilled(red area), so i know i do not have a refrigerant leak. Any suggestions would be appreciated, i just really hope it's not the compressor that would be a nightmare.

Dwes

To start grab a friend, start the car, and push the ECON button on and off while you're looking at the a/c compressor just to make sure the clutch engages.

Going through a similar problem myself. Turns out the high pressure switch (audi calls it the thrust sensor) went bad. It's mounted on the drivers side of the condenser. Only way to access it on the B7 is to take the front bumper off.

The best way to trouble shoot it for sure is you may need to pony up a few $$ and have an A/C guy look at pressures on the high and low side of the system with the A/C running. Using the over the counter stuff to fill the system isn't a good idea unless you can see pressures on both the high and low side with the system running. If the system gets overfilled you can damage the compressor. Other components that can fail and cause issues are the orifice valve (aka expansion valve) and the receiver drier (located by the front bumper, on the passenger side). In order to change either of those out you'll need to have the system evacuated and vacuumed, then refilled.