tazman

You can check if the waste gate is stuck open by starting the car up when cold and letting it idle, as the exhaust pipes get warm the pipe after the waste gate should stay cool.

Jason_86_951

Yes, good idea. John, do that and post results.
Jason

schnellfahrer

Sorry for the hijack, but could you elaborate on this?

Jason_86_951

Did the idle from cold to see if the dump tube warmed and it didn't. So the WG is not stuck open.

Other than a really weak spring in the WG, what else could it even be?

Cyrus951

Schnell,

Get a spray bottle and put a soap/water mixture inside. Spray the forumla onto all the vacuum lines, and with a cold engine, turn the car on, and look for bubbles. If you see bubbles, there's an air leak.

Danno

"but as posted before even when the WG line is clamped closed it won't boost more than 15psi."

So it's not a boost-controller issue then. Some cars with the Reliaboost can't get over 15psi even with the boost-controller cranked up all the way. I have an uipdated stifer spring for the controller that puts the adjustment in the middle of its range for 18psi. But pinching the hose shut should give you 25-30psi with the stock turbo and wastegate.

"Did the idle from cold to see if the dump tube warmed and it didn't. So the WG is not stuck open.

Other than a really weak spring in the WG, what else could it even be?"

Probably the wastegate at this point.

Mike1982

That is all I can think of is the wastegate but since you already changed it out 1 year ago, I don't know. Is there anyway you could swap out the wastegate and try another one? At least you could see if that changed anything.

awilson40

spraying on vacuum lines wont show a thing as they are under vaccum.
I meant you spray exhaust flanges, connections and even the header and cross over pipes.
You have to be fast and do it on a cold engine. Once the pipes get hot, it will burn off before it bubbles.
If you dont have any leaks, you might want to pull the WG and have a look.
The Valve could be stuck, the seat could have a chunk broken off, etc.
The only way to make sure is pull it and check the operation off the car.

Are you sure you dont have a pressure side leak?? Check and double check.
Do a search on pressurizing the intake. You could have something opening up only under presure.
I had just the vac tube come off the bypass valve and was only making 6 psi.

Jason_86_951

I did do a pressure test, got to 20psi and no leaks, other than the little bit out of the oil filler cap.

awilson40

Man.... sounds like you have eliminated bout everything.
Looks more and more like the turbo. The impeller on the hotside
could be damaged.

Sounds like its time to upgrade to the Vitesse Kit

Jason_86_951

John,
You hearing that???? UPGRADE TIME!!!!!!! at the least a K27/6 and Tial combo would do the trick

awilson40

I re-read all the posts, you said it has a gutted cat? what about a collapsed wall on the down pipe right befor the cat. Its been known to happen.

2+2

Take awilson40's suggestion seriously and get a cat bypass in there before you rip into the turbo. i have seen samples of the collapse. My car max boost was about 10psi which my tech picked up using the pinch the wastegate line test....got a Testpipe and its cured....dont know if my car had a clogged cat or a collapsed wall.

Jason_86_951

UPDATE:
We took out his gutted cat and put in a Bursch test pipe...........................problem solved! Boost for days!!!
The gutted cat doesn't look to be bad though, just too much backpressure I guess.
Thanks for the help guys!

Dark Lightning

I'd be willing to bet the upper cat-pipe looked like this: