I found a low side port under a switch near the top of the A/C run but it appears to be a fitting that doesnt connect to the ones on the bottles sold in stores. Is there a fitting sold to adapt these bottle fittings and do you know if the refrigerant wouldve been converted over from R12 to R134 refrigerant? Thanks friends.

 

The 95 A6 refrigerant is not supposed to be topped off through the low side port like many other cars. You are supposed to evacuate it with a vacuum pump and refill. Having said that, I did refill my daughter's '95 Audi 90 Sport Quattro a few times using a refrigerant manifold I purchased at Harbor Freight. That was some years ago so I do not remember the details. I think I may have filled through the high side port when the car was off.

 

It needs an adaptor that screws on to fill. Its not the pop on type of adaptor that refrigerant cans come with.