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Discussion Starter · #1 ·
So a few days ago i was on the dyno and half way through tuning my car just stopped building boost on a pull... than next pull it went up to 6 lbs, next pull after that it makes 0.5 lbs max. I just replaced my wastegate with a brand new ultra gate 38 turbosmart and made sure everything there is set up properly, I did about 10-15 boost leak tests and sealed up the small leaks that were discovered (this was a pressurized boost leak test). My turbo is pretty much new, all my parts are from Joe so theyre in good shape. I checked the turbo and there is no shaft play and it spins freely (yes i checked both sides of the turbo). I dont have a clogged Cat because i dont have one. WTF is going on??!! I'm pretty mechanically inclined and I have no idea wtf is going on now at this point. I've put over $24,000 canadian into this car over the past years and i'm shitting myself.

Any help is greatly appreciated..

Thanks,
Adrian
 

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check the bov
 

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there is a leak somewhere, if you replaced the wastegate, check that it hasnt loosened up on you, other places to check are the turbo to manifold bolts, stuck open wastegate, hoses from wastegate to boost source, if there is a check valve in the boost source line, it could be holding the wastegate open, Same with the BOV, if it is staying under vacuum, it will never properly close. easy check for either, pull the hose and see if you can hear or feel the wastegate or bov closing
 

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bout has to be in the wastegate then, I would think. I had a problem building boost, and it ended up being the wastegate to manifold bolts had backed out slightly and gave me a permanent exhaust leak. it also happened when I tried a copper turbo baseplate and wastegate gaskets, they got hot enough to become plastic and push out of the flanges
 

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Discussion Starter · #7 ·
bout has to be in the wastegate then, I would think. I had a problem building boost, and it ended up being the wastegate to manifold bolts had backed out slightly and gave me a permanent exhaust leak. it also happened when I tried a copper turbo baseplate and wastegate gaskets, they got hot enough to become plastic and push out of the flanges
Its definitely not the wastegate because i replaced with a new turbosmart one 2 days ago, all new gaskets and i can still see them sitting nice and tight in there when i look. Once again no boost or vacuum leaks... everything is hooked up properly. I have an hks evc-s boost controller i switched to wastegate spring pressure and it still doesnt spool. literally nothing. Its not the turbo too. Getting SO frustrated this is the weird problem ive ever come across.
 

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only thing I can think of then, is the valve in the wastegate may be stuck open, I know its a bitch to get to, but if you have no boost leaks, no exhaust leaks, and your vacuum plumbing is correct, there really aint much else it could be. even the bov, if it was leaking, you would find it on a boost leak check. if it was exhaust valves burned that bad, or jumped timing, the motor would run like crap, I would think. way you may check, remove the intake pipe and see if the turbo is spinning, if so rev the motor and see if it increases very fast, or if it stays the same speed. might need two of you to check this. if the wastegate is stuck open, the turbo shouldnt spool very fast when you hit the accelerator.
 

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Discussion Starter · #9 ·
only thing I can think of then, is the valve in the wastegate may be stuck open, I know its a bitch to get to, but if you have no boost leaks, no exhaust leaks, and your vacuum plumbing is correct, there really aint much else it could be. even the bov, if it was leaking, you would find it on a boost leak check. if it was exhaust valves burned that bad, or jumped timing, the motor would run like crap, I would think. way you may check, remove the intake pipe and see if the turbo is spinning, if so rev the motor and see if it increases very fast, or if it stays the same speed. might need two of you to check this. if the wastegate is stuck open, the turbo shouldnt spool very fast when you hit the accelerator.
If the wastegate was stuck open would it spool at all? I get 0-0.5 psi all the way to the redline. The motor is a fresh rebuild and joe is the one whos tuning it so things are pretty bang on. Ive checked off everything on the list at this point. :(
 

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If the wastegate was stuck open would it spool at all? I get 0-0.5 psi all the way to the redline. The motor is a fresh rebuild and joe is the one whos tuning it so things are pretty bang on. Ive checked off everything on the list at this point. :(
it may not spool at all, but there should still be SOME flow over the turbine blades, maybe enough to make it spin at idle, but if you press the go pedal and it dont spool up, well, at this point I would think wastegate. the turbosmarts have good reviews, from what I just quickly looked up, but that doesnt mean you didnt get a defective one off the shelf. Hope you didnt, and its just a plumbing issue!!!
 

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Discussion Starter · #11 ·
it may not spool at all, but there should still be SOME flow over the turbine blades, maybe enough to make it spin at idle, but if you press the go pedal and it dont spool up, well, at this point I would think wastegate. the turbosmarts have good reviews, from what I just quickly looked up, but that doesnt mean you didnt get a defective one off the shelf. Hope you didnt, and its just a plumbing issue!!!
So just checked the wastegate again, its in perfect working order. Something weird though is the valve is not getting pushed down at all, the inside of the wastegate is completely clean and so are the gaskets. wtf?? I can rev it to the redline and i get no boost at all. No leaks still... DA FUQ
 

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Make sure you EBC is connected correctly. If connected backward, vacuum may be holding the diaphragm open.

Edit: Scratch that, vacuum can't overcome the spring.

Something is wrong with the reference source, vacuum lines or wastegate. Double check those.

Sent from my Galaxy S6 Edge+ using Tapatalk
 
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