little trick

[B6S4John]

I have these valves, but they don't close at any revs. They don't seem to be stuck, because I can close them manually with my finger.
Can someone tell me were they are connected to the vacuum/engine, so I can check I've not got a leak.

[nidfix]

I have these valves, but they don't close at any revs. They don't seem to be stuck, because I can close them manually with my finger.
Can someone tell me were they are connected to the vacuum/engine, so I can check I've not got a leak.

The latest version of ECU program leaves them always open. May be that is the case for yours...

[cobraBLACK]

Sorry to resurrect this post but I just tried this on mine. The hose disconnection was fine but both my valves are stuck:

I haven't watched them with the engine revving but, engine off, one is stuck open and one is stuck closed and I can't move them with a screwdriver.

I tried spraying lithium grease (no WD40 to hand) all around the hinge inside the exhaust and around the actuator piston outside, waiting five minutes and pushing it again but no joy.

Anyone any suggestions?

[R33]

Yeah I have a similar problem. With engine off or on the left (NS) valve is shut and the right (OS) valve is open. Any ideas or is one just broken? If so can it be forced open?

[cobraBLACK]

I spoke to my dad this morning and he said lithium grease is no good - I need a penetrating agent like WD40 which will get into the joints.

I'll pick some up tonight.

Failing that, I might have to get medieval all over it's azz with a hammer and chisel!

[R33]

Tried WD to no effect, poked the valve really hard with a screwdriver and now it's open a bit, need to try again when I'm not wearing a suit! They seem to be jammed on both sides though, one open and one shut. If I can just get the shut one open then I'm guessing I don't need to bother shutting off the hoses as they are stuck anyway?

When the car is stopped with engine off should they be shut or open?

[cobraBLACK]

Tried WD to no effect, poked the valve really hard with a screwdriver and now it's open a bit, need to try again when I'm not wearing a suit! They seem to be jammed on both sides though, one open and one shut. If I can just get the shut one open then I'm guessing I don't need to bother shutting off the hoses as they are stuck anyway?

When the car is stopped with engine off should they be shut or open?

They should both be open when the engine's off and we should be able to tap them to move them closed; they should then flap back into the open position.

After 1700 RPM the actuator pushes them shut.

Looking at the diagrams from page 1 of this thread, it looks like a substantial amount of the flow is being restricted.

Audi - why?! Some people are saying for emissions, some noise. It could be either (or both) - although the newest software no longer shuts them, it could be that emissions were low enough for production to get the levels they wanted (for tax, PR, etc.) and now the valves aren't needed.

Who knows? (Rhetorical)

[1781cc]

Did this today, turned out that one of my flaps was stuck, Wd40, hammer and crowbar did the trick! All I did with mine is get some kitchen insert screws into the pipes, then had some silicone hose sitting aroun for the connectors which I put on with kitchen screws again. Two cablee ties and no one knows!

Results? Hard to tell, the noise difference is hardly noticable, maybe a little gruffer lower down the revs, doesn't seem and more powerful but does seem a little more responsive. My car has been mapped previously with gutted pre-cats, so maybe because of that the responsiveness is already tweaked as I think throttle agression has already been adjusted. What I will say is that giving it a go meant I noticed the stuck flap and for that reason alone it's worth doing as it's bound to hinder flow

[cobraBLACK]

Did this today, turned out that one of my flaps was stuck, Wd40, hammer and crowbar did the trick!

Did the same - just needed a crowbar and it creaked open.