Hesitation!!

Discussion in 'Modifications & DIY how-to' started by Goose013, Jun 12, 2006.

  1. Goose013

    Goose013 Member

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    I'm getting a hesitation when I take off or when I'm cruising and then mash the gas. It also does not seem as if the boost is spooling quite as fast and its really not maxing out where it should. Any suggestions? I have not made any mods to my engine lately with the exception of a Hyperflow tmic.
     
  2. Weapon

    Weapon 90lbs of dynamite
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    bad gas? Try resetting your ecu. Also going from a stock size TM to a big TM like the hyperflow you should get some tuning done. You could be ruinning lean.
     
  3. bluetwo

    bluetwo Active Member

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    I've always felt a little hesitation when I mash the gas on cruise control but I always thought it was just something in the electronic throttle. But I guess in your case it must be something else. (you have a cable throttle right??)
     
  4. jt money

    jt money 350hp mmm mmm Good!
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    i would do a once over on all vac lines around the turbo area. the one that connects from the boost soli to the wastegate can get quite brittle with all the heat in that area. its a start anyways.

    *edit kris is right tuning will probably clear this up.
     
    #4 jt money, Jun 12, 2006
    Last edited: Jun 12, 2006
  5. clemsonscooby

    clemsonscooby Active Member

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    Its summertime. My car feels a little slugish if I have been driving it for a while in the heat.
     
  6. miloman

    miloman Retired Admin

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    i second the summertime suggestion... i can notice a big difference in how my car pulls during the day and at night
     
  7. suby113

    suby113 Member

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    as long as the engine light isn't on I would do exactly what JTmoney and weapon wrx said to do. :p
     
  8. Goose013

    Goose013 Member

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    thanks, *the lines are fine, they were just replaced recently and I looked them over on the weekend. *Its not the weather because it was doing the same thing at night and during the day. I actually was expecting some weather responses; so good try...lol. *I do need a re-tune that's for sure, but it was running great last week.
    *As far as the gas issue that had crossed my mind also as I ran some Kroger gas of all things instead of my usual BP or QT, who knows.
    *My check engine light is on because of a cooling fan issue, but I'm working on that and haven't been in any traffic to overheat it.
    I'm going to put some booster in there along with some complete gas treatment and see if that helps.
    Thanks for the input so far
     
  9. miloman

    miloman Retired Admin

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    i doubt the bigger TMIC would make it feel sluggish without tuning... if anything i would expect it to overboost and run a little lean... then again, im no tuner :D

    see if u can get a hold of a logger and log your car... might just be bad gas that brought the advance multiplier down
     
  10. moose

    moose Infina Mooooooose!

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    Stupid question time, but why would a bigger TMIC cause a lean condition? I've heard this several times but I can't figure out why... the MAF should be metering all the air and adding fuel accordingly, so what am I missing in the equation?
     
  11. Goose013

    Goose013 Member

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    If I can get fan problem out of the way I'm going to save up for a tune with Scott S. I feel like my car is a hodge podge of upgrades right now and need to get it running right. hmmmmmmmm never had this problem before I joined wrxatlanta, my car ran great stock....lol ;)
     
  12. miloman

    miloman Retired Admin

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    good question... i never really thought about the MAF metering the air... maybe there's a scaling issue? maybe someone who knows will chime in
     
  13. siegelracing

    siegelracing Registered Vendor<br><b><font color="#666666">bion

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    Actually everything here is a possibility. Moose is correct that more flow doesn't directly cause a lean condition; the maf sees more air, then sprays more fuel...

    HOWEVER, Milo is also right that it "could" cause it to go lean because the stock scaling ends at 2.5 grams/sec/rev. Overboosting can put it off the table... what happens out there "off the table" could cause a lean condition.

    I would say that the car might be "mad" as in it has yanked the AM a bit, and now is running less timing...

    see if you can get some data...

    SS
     
  14. Goose013

    Goose013 Member

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    timing was my next thought but don't know how to do timing, anyone out there want to help?
     
  15. suby113

    suby113 Member

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    good question! thats what I thought also! I put a bigger intercooler in my 04 wrx and it didnt change a thing except for cooling capacity, I think.
     
  16. miloman

    miloman Retired Admin

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    what intercooler did u upgrade to? was it the STI TMIC or a bigger bar and plate?... the STi intercooler has a greater cooling capacity than the stock WRX IC but i don't think there's much change in the pressure drop... on the other hand, the big bar and plate ICs have a much lower pressure drop
     
  17. Goose013

    Goose013 Member

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    I think I have the same as you milo, I have the Hyperflow tmic. Its been running fine until now.
    on the way home the car felt so sluggish and would hesitate and backfire occasionally. Hesitations when I pressed the gas and then when I let off it would kind of buck.
     
  18. goixiz

    goixiz Active Member

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    poison pill


    dont forget the poison pill (restrictor)
     
  19. miloman

    miloman Retired Admin

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    i would recommend data logging it to see what exactly is going on
     
  20. Goose013

    Goose013 Member

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    how would I go about doing that?
     
  21. miloman

    miloman Retired Admin

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    find someone with delta dash or TARI... TARI is free but u need a cable to use it... so maybe u could download TARI and borrow an accessport owners cable
     
  22. Goose013

    Goose013 Member

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    you are speakin' Greek to me....I'll just post up a help thread...lol
     
  23. moose

    moose Infina Mooooooose!

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    Basically, you need a friendly soul with datalogging software and a cable to log what your car is doing and then look at the resulting file which might help indicate what's wrong.
     
  24. miloman

    miloman Retired Admin

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    hopefully someone reading this thread would be willing to log your car for you... i think thats the best way to start diagnosing the problem
     
  25. Goose013

    Goose013 Member

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    hopefully, thanks again
     
  26. Cool_____

    Cool_____ Banned

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    Tari is free and works great but is a pain to get set up right. You have to have a cable as well. My buddy has a Cobb Accessport and I use his cable when ever I want to datalog.
     
  27. suby113

    suby113 Member

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    sounds like he might have a bad coil pack, spark plug is fowling out, just my 2 cents.;)
     
  28. Goose013

    Goose013 Member

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  29. suby113

    suby113 Member

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    Cool man glad to see it was something very simple I will have to remember this.
     

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