I just bought a B5 S4 6spd monday. It's been a good car so far the only problem i've found so far is when i'm accelerating everynow and then the throttle completely dies to where i can push the gas pedal all the way to the floor and there's nothing there and then a few seconds later it comes back. I cant seem to find anything about this problem anywhere on the internet. Any help would be appreciated. Thanks.

 

sounds like a boost leak. when you push the pedal down and "there is nothing there", do your rpm's go up?

 

Nope the rpms start to drop untill it comes back.