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Thread: Engine wants to rev up off idle

  1. #1
    Fuel Injected!
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    Engine wants to rev up off idle

    Hi all,

    I've swapped a 1227747 $42 system into my CJ5 with an AMC 304. I'm a big fan of rock crawling, and I have a pretty low crawl ratio. The problem is that once I press the throttle off idle, the engine tends to rev up a bit. My theory is that the IAC is rapidly changing position and that's what causes the rev to happen.

    Is there a way to tone that transition down a bit so I can get a more proportional idle per given throttle position?

    thanks guys.

  2. #2
    Fuel Injected!
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    will be throttle follower steps for the iac when you tap it it extends iac so it doesnt try die on the way back down.if the settings defined in your xdf just lower the amount of steps it adds

  3. #3
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    Great! Will try this tonight

    thanks,

  4. #4
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    I decreased my max throttle follower steps from 80 to 60 and the idle surge has become much more manageable. Thanks again for the reply! I also did a bunch of research on the throttle follower logic and understand this much better.

    this leads me to a new question: now that I have less airflow off idle because of the fewer steps, do I need to adjust my VE table? I would imagine I'm running richer now I'm in that range. Correct?

  5. #5
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    It's probably fine would of shifted into a different cell than normal due to vacuum

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