Hey all, first off this is my first German car, and I'm loving it.
I bought this 93 Audi 100 quattro autothis year and have had no issues til a few weeks ago. When the car sits over night and I just jump in and drive it stutters and shutters for a few miles then it gets less, then in 5 minutes or so it's all good. I went to put gas in it the other day, and even with a half tank, when I took the cap off it had a big vacuum.
And after driving it, when it's off and I'm walking away I hear a whine from the rear end like the fuel pump winding up. Anyone have this problem before?

 

Did you ever find out what the problem is? I have a 1990 Audi 90 and it does the same thing without the noise at the end. Mine is leaking gas at the part right in front of the fuel injector. I have had miserable luck at getting any information on my car. I ordered manuals on line and either didn't get it or it came damaged.