Has anyone ever had a muffled clug, clug, clug noise coming from the rear of their A4?

[dmarotti]

I have a 2006 Audi A4 with only 28k miles on it. Recently, I noticed this clug, clug noise coming from the rear when hitting only some bumps in the road, or when down shifting hard (I have a manual trans.) Most people don't hear the noise, but I do. At first I thought it was a broken exhause hanger or something because it sounds like an exhause pipe sort of muffled bang noise. So I brought it to the dealer 3 times and they hear it too, but they cannot find it either. They said everything is tight; exhaust, bumper brackets, etc. I got under the car myself and can't find anything loose either. And there is nothing in my trunk, and the spare tire and tools are tightly secured. The only thing I suspected (without being able to verify this) is that when looking into the wheel well of the driverside rear wheel (where it seems the noise is coming from) I noticed that the strut housing tube appears to be movable. It is not loose from what I can tell, but I can swing it from side to side hitting the piston shaft. Is that normal for a strut? The passenger rear strut does the same thing, but there is no noise on that side; only the driver side rear. Any suggestions would be appreciated. Thanks.

[alisonj]

Hello - I'm not sure it's the same but I do sometimes get a 'thump' noise from the rear somewhere.

I just assumed it's the spare tyre shifting as I can't see anything loose and all the tools are secured.

Hope that helps
Alison

[P Smiddy]

I know this sounds a bit daft but i have the same problem, noticed it when stopping mostly.

I took the car to a quiet road and turned the engine off let the car roll a bit and then stopped.

Without all the engine noise i found out the it was just the fuel in my tank sloshing about usually happens when the tank is half full i have noticed and it sometimes gives a clunk sound.

Hope that kinda helps.

[JDS1985_B7]

I had the same thing with my 2005.5 Audi A4 2.0T, at around 24k when sitting at red lights or parked I would hear a "clug, clug, clug..."

Turns out it was a blockage in the fuel tank, and that is the air trying to displace the petrol in your tank. As the car uses fuel that fuel is displaced with air through a one way valve *as to prevent your car from blowing up if a spark were to get to the fumes* well that 1 way valve was / is STUCK and the clug you hear is air trying to enter your tank through the blockage.

better get it checked out...because not only is that valve serious, but it's restricting your fuel pump from freely pumping gas and in time will cause it to fail.. just about when your warranty goes out.

[Flakmunky]

You guys sure it isn't the spare wheel?! It is tightened down properly, isn't it?!

[randall977]

My A3 does the same - haven't tracked down the problem but someone suggested one of the rear suspension bushes - sounds sensible to me.

[dmarotti]

Thanks for all of the responses. I'm certain it is not the fuel tank issue mentioned above. While it may sound similar, my A4 doesn't have the same symptoms. I'm not sure I will ever be able to figure this one out. I still think it might be a strut cover becasue that is the only thing I can find with any type of play in it. Also, it seems that no one else notices it that doesn't drive the car regularly. So I guess as long as it is not damaging, I'll have to live with it; or, as my 19 year old son suggested, turn up the radio.