Jump to content
mpgscott

535d Rear Silencer Flap Operation

Recommended Posts

Noticed today a rattling noise off the rear of the car, its the exhaust inside the right rear tailpipe there is a flap thats in the closed position at idle which i assume is opened at revs via a vaccum.  Mine is free enough i poked at it with a screwdriver and moves fine.  Is there an easy way to test the operation can i get somone to rev the car and watch should it open and move?  Can you simply remove them as if its not opening it will hinder the power will it not?

 

Thanks as normal.

 

image.png.3ca1eae31d4e81d6afe9df8f51547cd7.png

Share this post


Link to post
Share on other sites

I think its vacuum actuated and stays closed normally unless you go over certain revs or in sport mode and then the vacuum opens it, check the vacuum pipe is connected to the actuator and doesn't have any splits, maybe also check the vacuum pipe back to the controller (not sure where it lives).

Share this post


Link to post
Share on other sites

The actuator is in the boot, opposite side to the battery, behind a side panel.

 

You should be able to just rev the car to see the flap open. However  I think it closes under vacuum and opens without a vacuum. If you simply disconnect the vac pipe (and traditionally block it with a golf Tee) then the flap stays open and makes more noise at lower revs.

Share this post


Link to post
Share on other sites
42 minutes ago, JasonH said:

The actuator is in the boot, opposite side to the battery, behind a side panel.

 

You should be able to just rev the car to see the flap open. However  I think it closes under vacuum and opens without a vacuum. If you simply disconnect the vac pipe (and traditionally block it with a golf Tee) then the flap stays open and makes more noise at lower revs.

That sounds like a plan, thanks for the information i will investigate..

Share this post


Link to post
Share on other sites

I don't even ask customers any more, when I do vac line work I remove that from the manifold by leaving out the T connector near the engine mount actuator, it fails open that way.

Share this post


Link to post
Share on other sites
17 minutes ago, GoNz0 said:

I don't even ask customers any more, when I do vac line work I remove that from the manifold by leaving out the T connector near the engine mount actuator, it fails open that way.

Is that in the boot of the car?  I thought it was an electric drive to control the actuator somone mentioned a golf T to block it.  Or is it a feed from the engine to the rear for driving it?  I will take a look..

Share this post


Link to post
Share on other sites

You will see the vac line heading up to the passenger side suspension turret. 

Share this post


Link to post
Share on other sites
43 minutes ago, GoNz0 said:

You will see the vac line heading up to the passenger side suspension turret. 

I’ve got this vacuum control in the boot that under this tray that looks to feed down to this.  So the feed from the engine your mentioning Gonzo is the feed to this actuator would that be right.

 

So ditch the front one and it will sort it.

 

Was thinking to just kink this feed down to stop it operating.

BEFD465F-68C3-4820-9C1D-6B6CBDBAC8F4.jpeg

Share this post


Link to post
Share on other sites
2 hours ago, GoNz0 said:

I don't even ask customers any more, when I do vac line work I remove that from the manifold by leaving out the T connector near the engine mount actuator, it fails open that way.

 

Yes , good call , the rattling was driving me crazy .

 

I did this years ago and problem solved ! 

Share this post


Link to post
Share on other sites
42 minutes ago, mpgscott said:

I’ve got this vacuum control in the boot that under this tray that looks to feed down to this.  So the feed from the engine your mentioning Gonzo is the feed to this actuator would that be right.

 

So ditch the front one and it will sort it.

 

Was thinking to just kink this feed down to stop it operating.

 

It's best to block or remove in the engine bay near the turret, less to leak that way.

Share this post


Link to post
Share on other sites
32 minutes ago, GoNz0 said:

It's best to block or remove in the engine bay near the turret, less to leak that way.

Perfect...

 

This the hose

image.thumb.png.1428447078cbc7d00cb84c14cc3c5ad5.png

Edited by mpgscott

Share this post


Link to post
Share on other sites

I've removed mine from the backbox, the flap i believe closes when the car is doing a regen?

Under the bonnet where does it disconnect from and did you just put a screw in it?

Share this post


Link to post
Share on other sites
4 hours ago, mpgscott said:

Perfect...

 

This the hose

 

Yep

 

1 hour ago, Mo_1986 said:

I've removed mine from the backbox, the flap i believe closes when the car is doing a regen?

Under the bonnet where does it disconnect from and did you just put a screw in it?

It's to reduce noise and it opens when the power demand hits a preset limit.

Share this post


Link to post
Share on other sites
1 hour ago, iReaper1157 said:

Is this just the 35d or does the 30d have it?

Pre LCI M57 have it m8

Share this post


Link to post
Share on other sites
1 hour ago, iReaper1157 said:

Oh. I’m LCI..... No idea what the engine code is. It’s a 30d anyway. 

M57n :)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×