TheMidnightSun

I just bought a used 2001.5 B5 S4, with about 66k on her. Since I just found my dream car, I've been out driving her pretty hard. If I quickly depress the accelerator over about 65 mph, the S4 begins to "chatter". It feels like I am driving over a poorly graded road or multiple small speed bumps. As soon as I release the accelerator the chattering stops. I have an aftermarket K&N Cone Filter as a replacement to the stock air box, which I recentatly cleaned. In addition the S4 is chipped.
Besides the "chip" and aftermarket filter the rest of the car is stock. I am currently thinking that it is an air flow issue, or MAS problem. Has anybody out there had a similar issue or problem? If anybody could help it would save me lots of $ in the shop if I could just do it myself. Thanks!

oldyellar

CEL on? either way VAG it.

Matt D (Charlotte)

I am having a similar problem right now on my 2000 S4 - it feels like any boost at all causes this chatter. Can you be more specific on what it sounds like? Currently the best advice going around out there is to VAG the engine (read the codes and figure out what the engine thinks is wrong) and do an intake pressure test to see if there are any boost leaks in the system between the turbos and the intake manifold. Email me and LMK if you figure anything out - I will do the same