AAC on 90% at idle

Discussion in 'Technical' started by bobert, Jun 7, 2014.

  1. bobert

    bobert New Member

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    Is there any reason for this? after doing my plenum pull the aac reading doesn't move from 90% and the car just slowly dies to a stall.

    No idea what to do now! :mad:
     
  2. TWIN TERROR

    TWIN TERROR Well-Known Member

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    I would guess that your base idle requires lifting due to a change after the plenum pull which may be due to you getting rid of a vacuum leak in the process. Reset your base idle then see what happens.
    Cheers
    Dave
     
  3. bobert

    bobert New Member

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    I won't save i've done it properly , but I did try winding it in and out just to try get it to idle at all, but it didnt make a difference, will try again tomorrow though!
     
  4. TWIN TERROR

    TWIN TERROR Well-Known Member

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  5. bobert

    bobert New Member

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    the connectors are the right way around, but I had them the wrong way around in my mind when i was trying to adjust them recently, i thought the blue (bottom) one was the AAC , Whoops.

    Hope this fixes it.


    also got some bad sounding noises coming from the top of the engine when its coming down in revs, not sure what it is yet, but i think its a problem for another day :(
     
  6. bobert

    bobert New Member

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    well I did the idle reset , eventually got it to idle but had to unscrew the screw so far that it was about to fall out so I don't think its right, and when I got it idling I tried giving it abit of a rev but it would hesitate and not rev up freely .

    any ideas what to try now ?
     
  7. bobert

    bobert New Member

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    unplugging coil packs doesnt seem to make a difference either :confused:
     
  8. SIM300

    SIM300 FAKE MODERAT0R

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    Hard to help on the keyboard. Was this issue present prior to the plenum pull? Always best to start with the easiest things and slow make your way through the list of things to check. You say there is no different with the coil packs unplugged? No difference to what, it not running???

    Perhaps get some local Z people over and have a tech day & see if a few more heads can help nut it out.
     
  9. rob260

    rob260 Administrator Staff Member

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    Exactly -the AAC value you can see is the ECUs "response" to idling conditions...

    I'm betting you've left something unsealed/unplugged when you did the plenum pull. Check all your vaccum lines, every single one. Especially if you did any deletes or modifications.
     
    Last edited: Jun 8, 2014
  10. bobert

    bobert New Member

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    Yeah I know its hard over keyboard, especially since im no good at explaining things!

    the issue before the plenum pull was 2 faulty injectors but it still drove around alright .
    I've replaced all 6 with another set of the exact same ones and put a new set of fuel rail - plenum seals in and a new manifold gasket , Also a set of copper BCPR7ES 0.8 gapped spark plugs .

    Im pretty sure the new set of injectors are good because the old set used to spit unburnt fuel out the right hand side of the exhaust at idle and there was always a stench of fuel , now theres no black fuel on the ground or smell.

    But now when I turn the key it will start up and run at about 900 rpms and with in about 10 seconds will slowly just drop rpms until it dies. Theres no audible air leaks and im sure everything is plugged back in properly because the cars had most of the deletes done so there isnt that much too the pull.

    I got the car idling before after unwinding the screw almost all the way out . but have put it back in since cause thats obviously not right.

    and I started it up and held the revs on by pulling the throttle cable and then pulled the injectors one at a time and there was no difference :S
     
  11. bobert

    bobert New Member

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    I've done it 2 times now and I was sure not to miss anything the 2nd time, but its still running the same . everything has already been deleted so theres a bunch of unused plugs in the engine bay, not even sure what all of them are
     
  12. tassuperkart

    tassuperkart Its a lie I tell you!

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    Do you have a Nistuned ECU?
    Were the injector you took out definitely stock and not bigger.

    Otherwise check your CHT connectors for integrity and cleanliness. if the ECU see dodgey figures from the CHT, it will revert to a kind of failsafe which is not fat enough to run it happily cold but should come right when hot.

    E

    E
     
  13. bobert

    bobert New Member

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    Yeah its a nistuned ecu, Ive got a spare socketed ecu that i swapped over last time and it didn't make a difference either.

    the injectors i took out were 800cc venom ones and replaced them with the same 800cc ones, What are the CHT connections ? I gave all the connections a squirt of CRC maf cleaner while everything was apart but nothing was corroded.

    its the same cold and hot
     
  14. rob260

    rob260 Administrator Staff Member

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    Why did you change the injectors?
     
  15. TWIN TERROR

    TWIN TERROR Well-Known Member

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    There is a great fault finding post in the Tech Section if you type - idle problem - it walks you thru it. The fact it improves by winding the screw out sounds like a vacuum leak.
    Cheers
    Dave
     
  16. bobert

    bobert New Member

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    The old set were leaking and ben said they were great injectors so he bought another set but never got around to installing them
     
  17. bobert

    bobert New Member

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    you're right thats a great guide, I think ill pull apart the aac unit tomorrow and give it a good clean up
     
  18. bobert

    bobert New Member

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  19. syntax_X

    syntax_X Zed Head

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    Well your tps is set correctly, your battery's charging and your afm is reading correctly.

    Maybe do a quick smoke test to check for leaks??
     
  20. strange zed

    strange zed Member

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    need to do a boost leak test dude u wont hear much with it idling in way of air leaks unless they are huge
     

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