Can't boost past 4-5 psi

Discussion in 'Modifications & DIY how-to' started by jautry27, Jan 16, 2014.

  1. jautry27

    jautry27 Member

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    All of a sudden, after shutting my car off, I started it back up, and now I can't boost past 4-5 psi. No CEL. I checked all the lines from the BOV and turbo and everything seems to be properly intact. I can tell its not the gauge because the BOV is noticeably softer. Car otherwise accelerates normally with no stutter. Only thing I could come up with off the top of my head is possibly the boost control solenoid.

    Ideas?
     
  2. superhawk28

    superhawk28 Member

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    Boost leak most likely. Many possibilities. Are you stock TMIC? If so check the y pipe under it....its a culprit.
     
  3. jautry27

    jautry27 Member

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    Yes, it is stock TMIC. I reckon I'll head down to the shop and dissect it. A couple of guys over at NASIOC suggested it may be a wastegate issue. Possibly stuck open.
     
  4. J_P

    J_P I like pudding pops
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    both are possible. Where are you reading the boost pressure from? Wastegate spring pressure is around 7ish psi isn't it?
     
  5. superhawk28

    superhawk28 Member

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  6. jautry27

    jautry27 Member

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    Just took the heat shield off. Retaining clip is intact. Movement and return of the arm seems normal. Replaced gasket from BOV to TMIC. All hoses and fittings are intact. Will drive and see.
     
  7. goixiz

    goixiz Active Member

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    BOV or BPV ?
     
  8. jautry27

    jautry27 Member

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  9. jautry27

    jautry27 Member

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    No change after driving
     
  10. Sparta

    Sparta Active Member

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    Leaking BOV, try putting the stock one on and see what happens
     
  11. jautry27

    jautry27 Member

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    I have a bluetooth scan tool that has the ability to read boost, temperatures, HP/Torque, RPM's and such. The boost readings are spot on with the gauge. I pulled the heat shield off and the waste gate arm is intact. Checked all hoses and none are torn or cracked. I replaced them all when I put the new motor in last December. I have since put about 30,000 miles on it. Like I said, it happened after I turned the car off. I shut it off, and about 5 minutes later, turned it back on, and that is when I noticed the reduction in boost. No CEL. No abnormal noises from the turbo.

    I'm beginning to think it's the solenoid.
     
  12. goixiz

    goixiz Active Member

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    change back to BPV
     
  13. jautry27

    jautry27 Member

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    I'm trying to sell my HKS so that I can go back to OEM. Although I do have the adapter to go full recirculation. I reckon I'll try that first.
     
  14. Jake

    Jake Active Member

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    Full recirc won't help if it's leaking. Aftermarket bov's are notorious for leaking. Had a Greddy myself that leaked only after 14psi, even completely tightened down. You should be able to find a stock BPV around somewhere for cheap or free.
     
  15. Sparta

    Sparta Active Member

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    yea, could be the actual diaphram in the HKS, in which case, you'd be selling someone a paper weight. This is all speculation of course, only way to test is to either pressure test the system or swap on the stock bpv.

    Ask AllPro for help.
     
  16. jautry27

    jautry27 Member

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    I filled it slap up with gas this morning and 15 miles down the road it started running fine. 12-13 psi. Bad gas maybe.
     
  17. integroid

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    Bad gas wouldnt have anything to do with your car not creating the target boost pressure.

    Like others have said I would check the BOV. I am sure if you ask around someone here has a spare one they would let you borrow or buy cheap.
     
  18. jautry27

    jautry27 Member

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    I didn't think that would cause it to do so either, but sure as shootin, as soon as I filled her slap up this morning, she went back to normal.
     

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