S3 Stock Exhaust


Registered User
Hi Guys

I've noticed a clicking/metal noise whenever i step on or release the gas pedal. It's pretty noticable when then windows are down so I took it to the Audi dealers to have it checked out through the warranty.

They have come back advising that this is a normal S3 exhaust issue. The twin pipe is like a fake and in reality it only uses the one pipe. The clicking noise is the sound of a value opening and closing to control this mechanism. According to these guys, who seem pretty decent to be honest, the exhaust behaves in this manner to give it more grunt.

I questioned this as I felt it was hard to believe but they assure me that this happens on all S3's, even one they had in for servicing. Can anyone else confirm if this happens on theirs also? I definately cannot hear anything on their A3 and A4 Diesel loan cars.

At the end of the phone call the options available to me are:
1) Remove the noise by removing the mechanism (which will reduce grunt of the exhaust)
2) Remove the part and 'grease it up' (maybe not quite those words) which will reduce the noise

So I am keen to know:
1) if this is fact or BS
2) are there any other options I can take now, as the noise is quite irritating to be honest (i know it sounds anal)!



Registered User
I have a 2006 A3 2.0T and I noticed this same noise as well when i had a cat back exhaust on my car, but as soon as I threw on a down-pipe the sound seemed to be more faint.

iono if i might have tone the noise out but i have a 3" down-pipe with stock OEM cat-back and the car sounds excellent and performs well
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VCDS Map User
There is an air operated butterfly valve in the left pipe of the S3 stock exhaust.

He is right in that they do break!

He is not right when he says you will lose grunt as the valve will manually get pushed open when you are revving the engine.

Since the car is under warrenty, I would have the exhaust replaced.

Or, get under the car, remove the air pipe (just pull it off), plug it and cable tie the valve open so you get the "grunt" all the time.

Easy job, I did it to mine prior to buying my Milltek and the car sounded a lot nicer!


Registered User
Thanks Redline - something to think about!

Boydie - So that noise is only when the butterfly clip is broken? Dam it, I wonder why Audi won't just replace it under warranty by default....


Registered User
I would get it replaced under warranty, and then do exactly what Boydie says and pull off the pipe and stick a zippy tie round it. That way you can revert to standard as and when u sell the car while getting the better sound now!