2.0 TFSI Problem

Sounds like the dump valve has gone

Faulty Diverter Valves are common on the MKV Gti.

I had mine changed as a precaution when I had REVO Stage 1 installed.

They are £25 from VW and arent that tough to fit.

VW upgraded these at least once by changing the diaphragm material as its a known fault for the diaphragm to split and leak boost. It also has a stronger spring.

IIRC they are accessed from the driver side wheel arch with the liner and wheel removed.
Its 30 min job for someone handy with the spanners and a trolley jack. My local REVO agent did mine for me, cost £20.

As soon as the MK5 have running problems this is the first thing they change as it cheaper than a diagnostic and will need swapped at some point anyway.

If you get stuck UKMIVS has a MK5 forum which is very good. Loads of help available, if you search `DV` you should access loads of info (and probably loads of my posts/tells of woe!)

Good luck

Paul

Had rummage in garage and found old DV.
Perfect working order, only done 15K before I changed it (needlessly as it turned out).

PM me if you want it and I will drop it in the post.

cheers
Paul

yep, its the diverter valve. the rubber diaphragm has torn and boost is leaking out.
design fault, the dv is located too close to the (hot) turbo.

my brother's gti has blown 2, for the third one he got some kinda uprated OEM version of it, apparently theres quite a few revisions.

in case you wanted to see, here is a pic of the last one that broke (apologies for the quality, i don't have a real camera with me now)