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    Hunting/Surging Idle

    Alright R3v, I'm out of idea's and turn to you all for help.

    I just finished rebuilding my S14, and I cannot get it to idle. After a cold start it will idle high around 2000-3000RPM for a bit then start hunting between 1500-2000RPM and finally come down and start hunting at 1000-1500RPM indefinitely.

    The high RPM's I am guessing are a combination of me not able to set the idle yet and cold start enrichment, so I am trying to solve the hunting issue first.

    What I've done so far:
    -Check my TPS, clicks when at idle and I get resistance between the idle pins.
    -Check my ICV, ~ 23 ohms across pins 1&2, 2&3 and ~ 43 ohms across 1&3 so that appears to be good. It also buzzes with the key in so that means its getting power. The rotating valve inside also spins freely and is not stuck.
    -Visual inspection of the ECM/Motronic transistors that control the ICV look fine. I could not test them since I am unsure how to take the top circuit board off to access them and don't want to break anything.
    -Check for vacuum leaks multiple times, an seal everything up. I do not believe this is the cause, as it would have to be a substantial leak for this much variation and should be obvious at that point.
    -Balance all the throttle bodies.
    -Replace the ECT.
    -Check fuel pressure, I have 43psi at the rail.
    -Check injectors for firing, I measured the output of all of them during cranking and they are all similar and not clogged.
    -Test the AFM as per here:http://www.the944.com/afm.htm.
    It seems to be working correctly with the output voltage rising as the door is opened and not dipping anywhere in the path.
    -Also O2 is new.
    -Injectors were new last year.

    Video here: http://vid575.photobucket.com/albums...912_143700.mp4

    I am straight up out of ideas, any help welcome and would be very appreciated.

    Thanks
    Shaun
    Last edited by s14pwd; 09-25-2015, 05:14 PM.
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