[greenphotos]

Ok, so I may not be an expert, but I'm sure I have never heard of someone having this problem before.

I'm sure some of you wonderful people (blatant suck-up ) will be able to advise...

When I release the accelerator (and there for the wastgate de-pressurises the system) I hear the normal Whoosh sound of the BOV. However, now, I also hear another sound after it, that is quite hard to describe so please bear with me. Imagine the release of air, in little bursts, at a high frequency of bursts. Loudish at the start, then gradually getting quieter. The whole event is over in about 1-2 seconds. I can replicate it again easily by boosting, then letting off the gas. Seems to do it more if I let of quickly, rather than slowly. Remember, I cannot hear the really sounds due to wind noise. Can't test it at stand still as the boost pressure doesn't build enough.
Boost to about 1 bar.

No mods to engine systems apart from Cat back 3"JT and nice blue vacuum lines.

My Simpleton's Diagnosis:
Could be the wastegate that at first opens wide to release the pressure, then hasn't got enough pressure to open prperly, so has to wait a few milliseconds for the pressure to open it.

Any help or advise would be GREATLY appreciated.
(Also if I do need a new wastegate/BOV has anyone got a spare?)

Mark

1994 9000 Aero

 

[mark e]

I think your diagnosis is pretty close, Mark.

A simple view:

Turbo is spinning, close accelerator, pressure builds up, DV opens, releases pressure, DV closes, turbo still spinning, pressure builds up, DV opens...

 

[greenphotos]

Originally posted by Mark E:
[qb]I think your diagnosis is pretty close, Mark.

A simple view:

Turbo is spinning, close accelerator, pressure builds up, DV opens, releases pressure, DV closes, turbo still spinning, pressure builds up, DV opens... [/qb][/b]

Thanks, so would you think it is a fault with the DV?

 

[mark e]

It might be, but I'm not sure. The easiest thing would be to borrow another one to try.