I have an HKS SS and it quit working I also have an annoying flutter noise between shifts when there is supposed to be a Whoosh from my BOV....I checked the forums for explanations...checked all hoses...it all checks out. Took it to the dealer and they are really cool about it, I told them to check the wastegate and noticed that it wasn't moving at all...but I never noticed a change in boost ever...but this little sllver wastegate is stuck and doesn't move. So they ordered me an entire new turbocharger and its all covered under warranty. Too bad they couldn't put an STI turbo in there.
Flutter is bad.
D