I was needing help with the A/C system.
1996 Audi A4 2.8L 8v
Were is the Low pressure side connector?

 

I'm not sure on that car where it is located, but it should have a blue cap on it I believe. The cap would have an "L" on it. It should be near the passenger side of the engine compartment

 

use the search function my friend, 1996 a4 didnt have the traditional low side port. apparently you can only fill at teh dealership through the high side port, what i did on my old car though was got a die and tap set and just rethreaded the audi low sid eport to accept a gm r-134a fitting.