help...the S is only pulling about 10inHg at idle in drive upon start up....

[Blue_S4]

when i get moving, it will drop to 20 while coasting, and then at a stop sit around 15 in drive. There is hesitation from about 20-40 mph, like a shudder thing, but no misfires at all. its not boosting as high as normal, only about 8 instead of 15. Then at above 40, there is a high pitched whistle when i use the gas.

what do you guys think? anyone experience similar problems? I am saying the whistle is not the turbos because its only when im going over 40, maybe im wrong. I would assume vacuum leak, but would that cause a shudder and loss of boost, or should i be looking more for a boost leak?

help much appreciated.

[A62TURBO]

I would assume vacuum leak, but would that cause a shudder and loss of boost, or should i be looking more for a boost leak?

You magically answered your own question, find that leak.

[Blue_S4]

haha...yea, but how?

[RolledMySTi]

Pressure testing time