toddk911

Well, just fixed some vac leaks and was getting 18 on vac guage and was making/holding my standard 17/18 psi to redline.

Just changed out my DV for the new EVO Billit unit and still fine as of this weekend. Now today, I noticed I was only making about 15-16psi. Don't see or hear any leaks and still getting good vac readings. Tried turning up the reliaboost and still only about 15/16psi. Put back in the old DV to be safe and no change. Also, the 15/16 psi that it is making, is holding to redline.

FYI my current GURU wastegate and turbo have made 18psi+ and held to redline so I would assume a boost leak somewhere and not wastegate or turbo "running out of steam". Also, the Venturi lines are bypassed and not an issue.

Any other ideas or best place to look for leaks??? i.e. are there boost specific leaks that would have no effect on vac readings???

theedge

Look around where you fixed leaks, maybe you bumped something loose or flexed a hose enough to crack underneath?

Jake951

Check all those small hard plastic lines that come off the intake manifold and fan out all over the place. I had one pull out by accident from its rubber fitting when I replaced my CBV and I immediately lost 5-10 psi of boost (no change in idle, though).

Sami951

I had a crack in the rubber joint/hose that's between IC and the hard pipe coming off the turbo. Couldn't see it until I took the piece out... it didn't seem to affect vacuum, but boost came on a lot later and peaked 2-3 psi short of what it was supposed to be.

toddk911

OK, thanks, I'll get looking into those areas.

MPD47

Yeah... ummm... I still havent figured out why I cant make over 15psi.

toddk911

MPD: You running a stock k26/6 ??

toddk911

Found some small exhaust leaks, but filled them and still only 15psi. After doing the "wastegate check". I.e unhooking and running it, still only 15psi.

Porsche-O-Phile

Et tu Todd?

Don't feel bad - I still only get 1.1 bar on mine!

toddk911

Nope.

I thought by doing the wastegate check that pretty much narrows things down but I guess not.

Jason_86_951

My friend Texasooner's 951 is doing the same thing. I tested everything I could think of, and have come to the conclusion that the turbo is the issue. Either that, or the WG spring has gave up the ghost from heat and has lost it's mojo.

MPD47

I blocked my wastegate and still only got 15psi. So I'm thinking it's my turbo (as i've checked around for vac. leaks) I'm hopefully gonna upgrade to John's Vitesse Stage III, so I wont have to worry about that much longer.

toddk911

Well my turbo is not stock and up until about a week ago made 18+ to redline. So not sure what the deal is.

Jason_86_951

Well correct me if I'm wrong, but if the bearings in the turbo start to lose their mojo it would decrease boost.
So would minor damage to the impeller.
Unless your "magic super boosting Guru wastegate" spring has broken or is stuck open, your turbo is on it's way to no boost land.

toddk911

Ok, gotcha. Not something I was hoping for!!!