sleeeperS4

Hey guys,

Since getting my S4 back from the dealer with a new clutch and rebuilt tranny, I've been having a nasty little boost problem. There are two symptoms I've noticed: In between shifts, the car is a complete dog! I realize you're supposed to lose some boost in between shifts, but this is a little extreme and it never did this before I got the car back from the dealer. Secondly, at the end of third gear, at around 5500rpms, I'm seeing the boost fall hard. You can also hear it die down from the sound the turbos make; the car just doesn't pull strong to redline in 3rd gear. As soon as you shift to 4th gear, you get a huge surge in power, i.e., more boost.

No codes with the VAG COM. Also, people have told me they've seen puffs of blue smoke out my exhaust under vacuum (deacceleration) but NOT when I'm on it full throttle. Does this make sense? I'm thinking it's a turbo on the way out, but this has been going on for a few thousand miles now and I've been checking the oil with no real sign of oil consumption.

I have an APR Bipipe and brand new TT BPVs which I just replaced last night. The problem's still there, though. :-(

BTW, all these tests were done with a 50/50 mix of VP103 unleaded race gas and Ultra 94.

Any ideas guys?

Thanx for any help!!

P. Bauer

make sure you have no intake/intercooler/bi-pipe leaks.

could be as simple as a hose, or as problematic as a blown turbo.

good luck.

TwnTrbo

If so, are you seeing the requested boost drop at all?

sleeeperS4

Do you happen to know what blocks I should be logging to see that? I remember seeing that somewhere, but didn't jot down which blocks those were...

Also, do most cars have identical actual boost and requested boost numbers at every RPM? Or is it normal to have a difference between the two at some RPMs?

Thanx!

P. Bauer

also, what chip are you running? stock?

sleeeperS4

I'm running XR and how big a pain in the *** is it to pressure test everything?

P. Bauer

remove MAF, plug breather tube coming from Y-pipe (driver's side) and then test away. You will hear the leak if you have one.

TwnTrbo

a quick search could fix that though...tons of info on logging in the archive

Avantgarde

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