vacuum pipe on oem rear silencer box

[MICHAEL PARKER]

When changing the oem exhaust for a bcs or similar i take it you should block the pipe off that was connected to the silencer pipe ?

 

[Bazzle]

On the S3 its there to open the 2nd pipe at different time, full throttle, idle etc.
So yes not needed on your new system, poke a screw and a bit of sealant in it.

 

[MICHAEL PARKER]

On the S3 its there to open the 2nd pipe at different time, full throttle, idle etc.
So yes not needed on your new system, poke a screw and a bit of sealant in it.

That's what we have done , just wanted to make sure it was the right thing to do .

 

[Whodafunk]

What pipe is this Michael? Is this something I need to do after my stainless being fitted last week?

 

[prt57]

What pipe is this Michael? Is this something I need to do after my stainless being fitted last week?

If you lie on the ground and look up in between the exhaust tail pipes near the rear silencer, you will see a small vertical rod attached to a lever on the outer pipe at the bottom and leading up to plastic vacuum operated valve above the pipe. The idea is that the valve opens and closes a flap in the exhaust pipe to comply with noise regulations. The valve is operated by a black rubber vacuum pipe about the thickness of a thick pencil. When fitting an aftermarket exhaust, folks block it up and cable tie it out of the way. Some people seal it with a screw or a golf tee.

 

[Whodafunk]

So if this wasn't sealed this would cause a vacuum leak?

 

[LEE69]

yes it would

 

[Whodafunk]

Is there a reason I can't see this on my car? Where they fitted to all models?

 

[Bazzle]

Only with factory fitted sports exh system.
ie. S models - Audi, R models VW

 

[Pergan]

Can i remove the whole vacuum belly or does it have any other purposes in the back of the car? where do i find it in the engine bay?