Yesterday I noticed this whistling/ grinding noise coming from the passenger side. I can only replicate the sound under heavy acceleration in 2nd or 3rd gear in the upper rpm's. At first I thought it might have been an exhaust leak, but now I am thinking it might be the turbo. Below is a video I took earlier tonight. At about 3 seconds in you can hear a whining/grinding/honking noise. Please chime in and let me know if you think the problem is shaft play or something else. Thanks in advance i-club!!

<iframe width="420" height="315" src="http://www.youtube.com/embed/pqozKt2h7BU" frameborder="0" allowfullscreen></iframe>

 

<iframe width="420" height="315" src="http://www.youtube.com/embed/pqozKt2h7BU" frameborder="0" allowfullscreen></iframe>

Embedding the video isn't working so here is the link: http://youtu.be/pqozKt2h7BU

 

Its a boost leak. Just had this exact problem. For me it was the bpv not completely tightened.

 

That's what I thought at first, but it isn't really a hissing sound like is usually associated with a boost leak. It's more of a honk and it only occurs between 4000-5000 rpm range. I would think a boost leak would be present throughout the power band but I could be wrong. I will definitely check the bpv, vacuum lines, ect for a boost leak to confirm though.

 

anyone else want to chime in?