[s-cars] off-boost stumble

[Noah]

Problem manifests itself when I am trying to drive the car gently. Somewhere
between totally off boost and 1.3 bar there is a little shudder/stumble that
makes the throttle seem like an on/off switch.
There is also a slight whistle that suggests a boost leak as well, but I
have been unsuccessful so far at finding it.

At WOT the car runs fine.

Ideas? Thoughts?


-Noah
92 S4 (soon to be all dooded up with Eibach/Bilstein HD)
84 UrQ