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robroy959
20-11-2007, 05:40 AM
I posted a question a while back regarding what I thought was a squeaky clutch on my 2006/56 2.0 SE Tdi Passat Estate (manual transmission) now with 11k on the clock. See http://www.vwaudiforum.co.uk/forum/showthread.php?t=15088.

I'm still being driven crazy by the noise :zx11:. It can vary from a low-pitched howl - which lasts for about a second - to an almost throaty sigh.

It's definitely not the clutch pedal or the clutch mechanism. It happens when the clutch pedal is pressed, but it also happens when I'm driving along and lift off the throttle.

My guess - but it is only a guess - is that something related to the turbocharger is causing the problem. Has anyone else experienced this or have any ideas?

Incidentally, on another website, a Passat owner complained of an "owl-like hoot" when changing gears. I reckon that this is the same fault as mine.

EDIT: I also found this post http://www.vwaudiforum.co.uk/forum/showthread.php?t=1497 on the Passat - General Topics forum which sounds as if it describes the same fault.

P.S. My local dealer hasn't been the most helpful when I reported it to them. The technician who accompanied me on a test drive claimed he couldn't hear it! Do VW supply their techs with heavy duty cotton wool for their ears?

BenR
20-11-2007, 09:51 AM
The problem is that you are accustomed to the background noise in your car and the technician isn't.

I believe the hoot and other noises are caused by the turbo wastegate blowing off pressure when you lift off the throttle. Try doing it with the window open as you drive alongside a wall and you'll hear it better.

Stuart W
20-11-2007, 08:25 PM
I drive the same model and know the noise described well.

I think there are two different noises - the 'owl-like hoot' when changing gear and a noise more like a small dog barking when lifting off the throttle, which I think sometimes occurs as a double 'bark' - woof, woof!

I'm not mechanically knowledgeable but the noise seems to be coming from the back end rather than the front (which makes the source seem even more mysterious). TBH I always thought it was just a natural part of the car's mechanicals rather than indicative of any problem, and the noise hasn't changed since new (I've now done 44k) and doesn't seem to happen all the time and I don't really notice it so much these days now that I'm used to it.

Before I got the Passat I used to hear larger commercial vehicles (small trucks perhaps?) making a similar if exaggerated version of the noise when they changed gear, and thus thought that the Passat noise is just a less obvious version of the same noise (this was early morning while lying in bed and thus no other noise to mask the vehicle's noise, thus it always seemed very loud in comparison to the vehicle's other noises!).

I've never mentioned it to the VW dealer though.