I am pretty sure its the diverter valve on the turbo that is working... I guess Audi switched from a diaphram valve to a piston valve in '09. This would explain why the noise occurs in newer models only. When the turbo is winding up but engine revs are down (ie/ little boost required) the rustling noise is the piston diverter valve shedding excess boost. At higher revs the boost better matches what is required by the engine and there is no noise.
Can anyone who knows a little about turbos confirm what I'm thinking? and what it be possible to switch back to the diapram version to 'stop' the noise (though I think the piston is a better setup, just annoying)? Let me know.
this noise you guys are talking about, i've noticed since my test drive. it's almost a month after my purchase and the noise still persists. i'm no mechanic but i'm pretty sure it has to do with the turbo. my neighbor has a 2009 TT and it has the same noise. it's noticeable under light to moderate acceleration (around 2500 - 3000rpm).
what about the slight poof you hear when the gears shift??? i've been told its the DSG fart. under hard acceleration in manual you can hear it when you shift gears.
This came to mind..If any of A3 owners have the S-Line exhaust tips.. U can hear them vibrating at 2500-3000 Rpm range... Yes the exhaust tips are not part of the muffler.. There sepperate pieces
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Re: New 09 A3 2.0T Quatro Engine Sounds?
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