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Something is seriously wrong with my car...please HELP!!!

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Old Aug 7, 2007 | 12:51 PM
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Default Something is seriously wrong with my car...please HELP!!!

So I have not been able to build any boost since i installed my turbo kit. For some reason my car is running super lean at WOT. (By super lean i mean 14 and up!!) I have tried adding fuel VIA emanage to no success. I have upgraded to a walboro 255lph pump, but i did not change any of the wiring. I just plugged in the new pump. Could this be my problem?? I am completely at a loss here. The only reason i can think that i am not making boost is because the car is running so lean. I have checked for vacuum leaks, and my turbo is getting oil and spinning freely.

the car....

1992 sc300
1jz swap
t61 single turbo
mkiv 550cc injectors.
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Old Aug 7, 2007 | 02:13 PM
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It certainly sounds like a boost leak to me. Try checking your couplers too, a friend's WRX looked all fine but had a crack in the back of one of the couplers that you couldn't see at a glance.
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Old Aug 7, 2007 | 06:47 PM
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i checked for a boost leak. Pressurized the system up to 25psi...no leaks!

Would the car run lean if there was a boost leak, or super rich?
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Old Aug 8, 2007 | 04:27 PM
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bump!! someone please help...
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Old Aug 8, 2007 | 05:17 PM
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your wastegate could be stuck open, check that and the vacuum line.
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Old Aug 8, 2007 | 06:26 PM
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wastegate is not stuck open, however i think i might be leaking around it. Would the vacuum line cause no boost? I was under the impression that the vacuum line would cause a boost spike.
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Old Aug 8, 2007 | 06:35 PM
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Check your manifold for cracks.
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Old Aug 8, 2007 | 06:44 PM
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You're running 92 ECU? Wasn't there some kind of a problem with that and E-manage?
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Old Aug 8, 2007 | 06:55 PM
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a vacuum line loose or leaking will give you low fuel pressure under boost....

do you have a boost gauge?
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Old Aug 8, 2007 | 09:25 PM
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I do have a boost gauge...it shows zero boost no matter the RPM
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Old Aug 8, 2007 | 09:35 PM
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Originally Posted by sc300gte
I do have a boost gauge...it shows zero boost no matter the RPM
does it also show vacuum? if so, does it show vacuum until you hit the throttle?

it sounds to me like you have a major boost leak, a stuck open wastegate, stuck open bov or something along those lines...
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Old Aug 8, 2007 | 10:22 PM
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it shows vacuum at idle...when i hit the gas it goes up I'm thinkin its something wtih the wastegate, or a crack in the manifold.
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Old Aug 8, 2007 | 10:37 PM
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Originally Posted by sc300gte
it shows vacuum at idle...when i hit the gas it goes up I'm thinkin its something wtih the wastegate, or a crack in the manifold.
it would have to be a serious crack...

back to what I said - major boost leak, stuck bov or wastegate...
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Old Aug 9, 2007 | 01:17 PM
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I pressurized the system to 25psi...no leaks!
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Old Aug 9, 2007 | 03:09 PM
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i'm with everyone else, even though you say you checked it
sounds exactly like when my coupler blew off. . .
but iunno how you'd miss a leak like that if you put a cap at the throttle body, and then compress air into it at the turbo. . .

i don't think a manifold leak would cause 0psi at high rpms.
and a wastegate stuck open would make the car much louder. . .
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