Boost dropped off

[rodpaslow]

Quick question - I have a vnt 17 I use both the control on the turbo and a wastegate to make sure it doesn't over shoot a set boost.  New motor-day three of driving it was a hot 27-29 (90 or so F) and was accelerating hard boost was at ten suddenly dropped to 2 psi (1050 egt or so when it happened).  Now driving it I can only get 2 psi from it.  VNT control is closed (for max boost).  Is the wastegate likely stuck open? Is there something else I'm missing?   (boost tubing and connection have been checked and are okay, as well as gage tubing checked and is good)

Thanks.

[JamesT]

Sounds like something has stuck open. A VNT 17 should be able to make more boost than that even if the vanes are in full volume position, it will just take longer. The waste gate is probably stuck open.  Does the engine have the BOV port on the intake manifold? It could be leaking from there.
What kind of waste gate are you using? Can you adjust it to allow more boost? Maybe the spring tension has backed off.

[rodpaslow]

I'm thinking same as you.  It's a cheap DNA wastegate.  the port in the intake has a o-ring and plug I got from Giles.

I think it's stuck open.  Do you know -does a wastegate like that have a metal diaphram?  I'm going to have to take it apart and clean it so i guess I will find out.  thanks!