Hey guys,

This afternoon I hopped into my car and pulled onto the road. When I accelerated past 2,800 RPM + a whining sound similar to a dental drill came from my engine. The response time and power for the turbo seems to be constant, or at least so tiny I can't tell a difference. Just before the whine started, I added a 104 octane boost to my tank and filled up the rest of my tank with the usual 91. I highly doubt that the octane boost has anything to do with it, but can't leave anything out I guess. What could this whine be? The volume of it gradually intensifies up to 4,000 RPM and then remains of a constant volume. As I said before, it sounds like a dental drill, or a massive turbo that sounds slightly off, and I am pretty sure no one snuck an old crappy turbo into my car when I wasn't looking .

I have a 2005 A4 Avant 1.8T (B6 of course) with a AFE stage II CAI, APR 1+ chip & APR fuel injectors... All of which have been installed at least 6 months ago. Hoping to do more soon, but that is besides the point.

What is wrong with my car? Simple fix hopefully?

 

That is usually the sound of the turbo going bad.

 

Took the Audi out for a long test drive this morning and determined the "drill" sound to be consistent with the gas pedal and not the RPM levels. The harder the press on the pedal the louder the sound, regardless of the changes in rpm (confused me before since higher rpm needs a deeper pedal press). This makes me think it is not the turbo, but instead possibly a belt? A friend also suggested it could be a blown diverter valve. Any new thoughts?

 

Turbo runs off of exhaust, not engine rpm (like supercharger). Probably less variance in exhaust pressure even though rpms change when shifting.