I am new to this forum and hope some BMW experience can help diagnose a problem I have, my mechanic is also miffed.
My car is a E90 320D SE, it lost 80% of power last week resulting in the AA telling me the turbo had gone. My mechanic replaced the turbo. As soon as the new turbo was fitted the car has made this terrible whirring noise, i have uploaded 2 vids to youtube see the links below,
First assumption was that the new fitted turbo must be faulty, it was sent back to the manufacturer who said it tested fine but sent a different one just in case. Same noise. The breathers were also replaced at the time of turbo replacement.
The noise is directly related to the revs and engine, ie. it still makes the noise when in gear with no gas but the engine is turning. The mechanic also replaced the crankshaft pulley, still noise.
I understand that when the boost pipe is disconnected and tested there is no noise,
The car actually drives fine with full power and behaves as normal apart from the loud noise.
Basically my mechanic is stumped and doesn't know what is causing this, i also now have a car that i have spent a lot of money on and is barely driveable, certainly not saleable. Is there anyone out there who has had a similar problem or has a suggestion to what is causing this? greatly appreciated. thanks in advance.