weird boosting

Discussion in 'Modifications And Maintenance' started by fino22, Aug 21, 2006.

  1. fino22
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    fino22 New Member

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    Recently when I accelerate at full throttle my boost gauge will fly past the .1 mark on my factory boost gauge to .12 then drop down to .07 or .08 then go back and forth on the gauge between the .08 mark and .1 mark as long as I am holding the gas peddle down. This only happens happens when I floor it so far. Any ideas. I never really see ever go past .1 on the boost gauge and once the boost drops it stabalizes and doesnt bounce back and forth like it has been.

    NOTE:
    -Only recent change to my car is I put on a APS TMIC (to get ready for upgrades)
    -4EAT Cobb Stg. 2
     
  2. DISCOPOPE
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    DISCOPOPE Well-Known Member

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    sounds like boost spikes.
    your controler is saying, "MORE BOOST MORE BOOST!"
    then because your moving air better with the up/down pipes, you shoot past the target and your boost controler says, "LESS BOOST! LESS BOOST!"
    then you dip below the target, shoot up over it, then back down......

    to be sure i'd check the vaccume lines from the wastegate to the controler to make sure they are not partialy crimped or anything.
    only other thing might be an actuator problem, but i'm not 100% sure how to check one without pulling it.

    be sure to include boost control into your upgrade. gain can be adjusted in the ecu, so unless you are going huge maybe all you need is one of the GM boost solinoids.

    -
     
  3. Imprezme02
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    Imprezme02 New Member

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    Shouldn't be the TMIC, I duno if you have the one from me, but I put it on my car near stock and drove to michigan with it with no problems or tuning.
     
  4. Xcelor8
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    Xcelor8 Well-Known Member

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    I wonder if some wastegate adjustment, would help.
     
  5. speedyham
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    speedyham Well-Known Member

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    Check all your vacuum lines. Sounds like you missed one somewhere.
     
  6. fino22
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    fino22 New Member

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    I actually think that one of the lines off the wastegate is crimped under the corner of the TMIC. I am going to go uncrimp it and see if this helps. That TMIC is so big it rubbed the ac line and caused a leak. Anyone know how much a new line costs.
     
  7. SUCKERPUNCH
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    SUCKERPUNCH New Member

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    The blue bird can sing, but the crow's got the sou
    No idea how much a new line costs, but you will have to get your refrigerant recharged, and hopefully you didn't lose any oil out of your compressor when all the refrigerant leaked out, or else you could smoke your compressor.
     
  8. Imprezme02
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    Imprezme02 New Member

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    Depends on the line, ask the parts department at Subaru. I just replaced a A/C line for $130. Yeah that top mount is the biggest one they make, you just have to be super careful puting it in, because obviously that a/c line that runs along the firewall is fragile. When it was in my car the line was sandwhiched in between the tmic and the firewall. I also noticed the wastegate vacuum line was goin to be smooshed so we extended the line a couple inches.
     
  9. Imprezme02
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    Imprezme02 New Member

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    They re-oil when they do a recharge, and once the oil isn't present in the system, if you try to turn on ur a/c, the compressor will not turn on. Safety measure.
     
  10. bikerboy
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    bikerboy Subie GOD Staff Member

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    Sounds like a leaky BOV to me I got your mail and you have the TXS that is known to leak. You can take the cap off and shim it with a couple of quarters.
     
  11. fino22
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    fino22 New Member

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    Thanks I will try that.
     
  12. fino22
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    fino22 New Member

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    I threw a cel today so when I checked my engine I noticed that the nipple that comes off of the stock wastegate broke off clean and the tubing was just hanging down. Is there anything I could do to patch it up until I get my new turbo installed which will be soon, I dont know how much pressure comes through there.

    I drove it home cause I was at work and the check engine light turned itself off and it drove fine under low to no boost.

    Anyways if I dont have to I would like to fix it somehow without having to pay a ton since it will be off my car soon.