mmi cold/hot idle probs

  • shanew
    shanew
    13 years ago

    hi all

    Got a prob with my 98 ultra mm efi cold/ hot idle.

    Have been through all reset procedures :ie tps voltage setup for cold idle no joy and by the rpm referance setup no joy here either.

    when going through the procedure at the start i notice the iac doesnt do the full retract and 100 step after i pull the fuse ,when i key on the procedure says it will do this once only when u key on the ignition,also when i unplug the iac(idle actuator control) to set the rpm for warm up it revs about 1500rpm which sounds about right for a cold start(i set that by tps voltage) when i plug back up and try it when its cold again no joy idles about 450-500 until warm idle takes over which is still abit low at 850rpm.

    i also notice the iac doesnt fully retract when hot until you blip the throttle ,i did a dtc code read off the engine check light and i can get the first digit its a 3 the second digit is flashin too fast it might be a 4 or 5 as far as i can see does anyone know the code 34 or 35 if its the idle control actuator i will know i found my problem as there are only 2 inputs to that idle control that i know of engine temp sensor and idle control actuator and of course ecm to add more fuel but i dont think its that.

    Any help from you guys much appreciated .I wont be doin a carb conversion efi is good just need to get my head around it.

    Cheers

    Shane

  • AJ56
    AJ56
    13 years ago
    Not sure of the code but it seems EFI have the same issue. Try cleaning the IAC with carb cleaner whilst operating the Kill switch on and off so the IAC retracts with the ignition on, It looks like it is not parking correctly after turning off. If that doesn't fix it maybe the IAC is on the way out. I don't know if you can bench test them though.