Vilooo

Hi, about a month ago i did a stage 1 upgrade by APR on my 01 Allroad. The car drove alot smoother until my left turbo blew. It started with a faint whistling sound under boost and grew louder the day it snapped the exhaust side shaft.
I have changed the turbos. however after about 150km of driving I'm noticing a whistling sound comming back again! I just inspected my left diverter valve and just by chance a bit of rubber inside hagging out. I think it is the diaphram in the valve. I think perhaps some has gotten into my new turbos and damaged it hence cause a whistle at boost again.
The Mechanic change all the oil feed lines to the turbos and replaced all the coolant.

Prospeeder

Well its always possible to get a defective turbo. Your using something like 5w30 or 5w40 synthetic oil? Allowing the engine to idle a minute or 2 on cold start? Allowing some engine idle time after a super hard run? Auxiliary After run coolant pump is working? Other than that, nothing really should have caused it to fail if he also did the feed lines.

And just to be clear, your not talking bout the normal turbo sucking whistle noise right, its clearly a grindy bearing sort of noise?

boost401

I have a whistle too under load..... Not boosting .... but I'm pretty sure it's normal

Vilooo

My whistle sound comes at around 2000 rpm and disapears if I accelerate hard! I have since driven the car hard and not managed to blow another turbo yet! today I'm putting on another APR program to bring back the ECU to original to see if this eliminates the sound. Will know in a few days.

Vilooo

I'm using Castrol Edge 0-40 and warm the motor up always and let in cool for ages before turning it off, its a faint whistle that is noticed whilst going throught the 2000 rev range and you can still here it whilst accelerating slowly only, if you drive the car hard you cant here it. Its also mainly noticably louder when the car is cooler and no its not the secoundry air pump.

Dustbuster

My engine started making the same sort of turbo noise around 100,000 miles. Our other car has a turbo from a different manufacturer (not and Audi) and it began a noticeable turbo noise around 70,000 miles. I suspect the vanes wear and start to create noise or something (no idea, but all the mechanics say everything is fine), but that doesn't explain your new turbo.

Jordan Strasser

When your turbo blew the first time did you loose all boost or did you still have boost from the one that was good yet? Just wondering because I just had a turbo blow and I believe it's only one but my boost gauge reads zero boost. Thanks!