Dumping boost

[GTIdanman]

Have just noticed after taking my car out for a blast that it seems to be dumping it's boost at about 4000 revs! It accelerates up to 4000 the it's stops pulling and I it sound like the dump valve is stuck open. It's a constant whooshing until I take my foot of the accelerator. Could this be an ecu issue?

[GrayMK5GTI]

Could be your Divertor valve has split. Common problem 

Try the search function for more info 

[biffobear]

Boost leak?

[GTIdanman]

Any idea what the cause and solutions could be? I have noticed now that it's not always 4000 rpm and it intermittent. Doesn't happen all the time. It's a strange one!

[MC71]

Check/change the Divertor Valve. 

[Scottymon]

Have you checked the DV as suggested mate?  Most likely that or some other boost leak.

Is it mapped? Could be the HPFP straining to give you enough fuel.

Visually check the DV and or have it scanned.

[GTIdanman]

Have had a quick check over it but can't see anything obvious. Haven't had it mapped yet. Trying to find somewhere cheap enough, everywhere around by seem to charge silly amounts. Think I'll go get the DV replaced see if that sorts it. Thanks for the info guys.

[dansmith180]

Always go for a live map, especially if you're having this issue, they'll give your car a full health check before cranking up the power.

[GTIdanman]

DV changed.... Problem solved!! :)

[PaulED30]

I also need help with boost dropping off, not sure if it would be the DV as it has been changed In the past to rev g and car is only just on 40k.

If I set off in a spirited fashion 1st gear is fine, then change to second and it seems to die and then catch itself back up but doesn't accelerate as I would expect. If I'm already in second and then put foot down it seems fine, haven't noticed it happening in any other gear though.

Is there anything else it could be other than the DV?
Is there anything else I should check?
Would it be easier if I just found someone with vcds?

Thanks

[PaulED30]

Sorry for the bump, but could do with some help

[Georrge]

Sorry for the bump, but could do with some help

First of all check your DV to see if that's the problem. Just because it has been changed before, doesn't mean it won't split again 

[PaulED30]

What do I check as I don't think there's any rubber diaphrams? There Is a picture of one here

http://www.mk5golfgti.co.uk/forum/index.php/topic,63726.0.html

I've taken it out before to check but just looked at it seen it was rev g and just put it back in

[GTIdanman]

I had a loud hissing noise coinciding with my boost loss. Turns out there was a 4mm hole in the rubber diaphragm. Since putting the revision G on it like a new car.