I just bought a 94 S4,

the problem that I am having is as I hold the throttle (like on the highway) over 2200 RPM it loses RPM and gains RPM all within seconds, and this happens all the time, anyone have any ideas? now this doesnt just happen on the highway, also city driving when ever i hold a constant speed or rpm over 2200.?

 

I'm not familiar with the model, but I was thinking a fuel pump problem or maybe you need new ignition coils.

 

Well, my thoughts would be a fuel issue. Either bad fuel pump..or you have bad fuel itself... something along those lines where your getting fuel cut under throttle...

 

it might need a new fuel filter or throttle body cleaning out or both

 

I dont think its the fuel pump as when i accelerate it is fine, and I have tested the coils and they are fine, it only happens when holding rpm

 

sticking throttle flap comes to mind