Compressor surge?
Compressor surge?
Perhaps I havent notcied it until now, but when throttling back during light accel or when shifting I consistently get this soft fluttering sound. The best way I can describe it is "fthththththth". Its hardly noticeable most of the time. If I'm on it and I upshift quickly, it becomes harsher. If I completely drop the throttle between shifts, its almost a shriek. I do have a Bosch bypass valve installed, and its working correctly. The noise almost sounds like a peice of rubber flapping, like I've got a loose coupler and its farting a little bit. But if I get under the hood, rev it and quickly close the throttle the sound seems to come from the compressor inlet. Its almost a bark if I rev it hard enough before I clam the throttle shut. The BPV is bypassing at the same time, quite a lot actually, but the sound still persists. Am I barking up the wrong tree or does that sound like surge? Maybe I need an additional bypass valve? It runs hard under WOT, no problems until I throttle back. Around town its fine until I lift the throttle to shift, then I hear the flutter.
