Small pipe going to "nipple" on throttle body / inlet manifold

[ya53lhd_MATT]

What is it, it does down to near the horn? Seems to be restricting the revs on tick over, suffering with a lump idle on tick over (just been rebuilt) When i take this off, it grabs back say another 100 rpm, but is still slightly lumpy, when i put it back on, it starves it slightly.

Any ideas?

 

[MarcB]

I might be wrong but i think its something to do with the Acoustic Valve down next to the horn at the back of the passenger headlight

 

[lemonnobby]

correct it is. not your fault i wouldnt have said. timing correct with the correct tools

 

[ya53lhd_MATT]

yeah correct locking tools Lemonnobby1, runs fine once you pull away over 1000rpms?

 

[MarcB]

I dont have an Acoustic Valve in the Trophy but when i followed the pipe from the throttle body thats where it went too and mine has a small bolt in it to block it off.

 

[ya53lhd_MATT]

What does it do, if it's no needed?

 

[Tunst]

Its to do with induction noise levels iirc

 

[Gandi69]

Yeah as above. However removing it supposedly has no benefit at all, apart from losing some weight obviously