i have a 2000 audi a4 1.8t auto

with an apr chip

it boost properly everything for the most part runs great

but when its boosting hard it makes a weird almost whistle. not like an air leak but like kinda the sound a whistle makes like the metal ball rolling around inside. has anyone ever had this problem before? i had teh shop check for air leaks and there are none. its just a really loud sound that i am almost positive is different from that of normal turbo boost!

HELP!

 

Thats the sound you get when a turbo the size of your fist is pushing 15+psi.
The ball rolling around sound is sort of odd. Does this only happen after a cold start and get better as the car warms up? Stay off heavy boost until the engine has had enough time to warm up/cirulate oil through the system.

 

it might be your waste gate mine made the same noise and was broken rattling around
dunno?

 

The rattling wastgate arm sound is usually only audible after a small rev while idling. Ive heard a couple A4's with that problem before though. Was that not the case for you?

 

when it would build boost it rattles like crazy for a couple seconds then when the throtle closed same thing but only made about 2psi most the time