AlanL

I recently had my turbos replaced (factory K03's) and am probably more paranoid about sounds from my engine than before, but there is a new sound that has me scratching my head.

When the car is already warmed up (engine oil at least 200 or above) and the engine is restarted, the first time that boost is requested there is a distinctive whoosh of air that can be heard from the passenger side of the car followed by a cessation of the sound and boost suddenly being increased. This only happens on the first such boost request after an engine restart. If I stomp on it after that has occured, I get boost as usual and there is no repeat of that until the next time I shut the ignition off and start back up again.

BPV's are Audi 710N's and I did try swapping the passenger side one out to see if that made a difference - it did not.

I presume that the sympthoms for a failed TBB would not be restricted to the first boost request like what I am seeing (hearing) right now, but would be more persistent.

Any clues to what I am listening to? I did search the archives for info on wastegates and what I could glean about this part of my engine's plumbing doesn't quite seem to apply.

TIA