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Thread: 7247 idle to off-idle question

  1. #1
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    7427 idle to off-idle question

    Hi all,

    Tuning the 7427 there are 2 parameters for the idle vs off-idle tables - speed and TPS %. Right now I believe the factory settings are 3mph and 3% TPS. My question is do both parameters need to be met to transition from the idle to off-idle table?

    Say I'm cruising along at 45mph and take my foot off the throttle - speed will be 45, but TPS will be zero. Which table would be in play? Likewise if I'm parked and I open the throttle so TPS>3% but speed is 0, which table will it be using?

    Thanks!

    Mark
    Last edited by Dieselsj; 03-05-2024 at 03:38 AM.

  2. #2
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    Bumping this as I still don't have a good answer.

    Quote Originally Posted by Dieselsj View Post
    Hi all,

    Tuning the 7427 there are 2 parameters for the idle vs off-idle tables - speed and TPS %. Right now I believe the factory settings are 3mph and 3% TPS. My question is do both parameters need to be met to transition from the idle to off-idle table?

    Say I'm cruising along at 45mph and take my foot off the throttle - speed will be 45, but TPS will be zero. Which table would be in play? Likewise if I'm parked and I open the throttle so TPS>3% but speed is 0, which table will it be using?

    Thanks!

    Mark

  3. #3
    Fuel Injected! MO LS Noobie's Avatar
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    I do not know the definitive answer to your question, but my my reasoning if either parameter is met it transitions. That means at 45 miles an hour, decelerating, with your foot off the throttle, it would still be off idle because your speed is exceeding 3 miles an hour. I would think that the PCM would try to bump base idle speed in that situation to give it a little more air so it doesn't decelerate so hard and possibly doesn't load up with fuel.

    I may be way off but that's my two cents worth

  4. #4
    Fuel Injected! ralmo94's Avatar
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    This is correct, if both are not below set value, it will use open throttle ve table. That is why I like to use trimalyzer to tune VE, you can just set a filter for idle flag false, then go back and change to idle flag true, and tune the idle VE
    No need to re-invent the wheel. But we can make it better

  5. #5
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    Quote Originally Posted by ralmo94 View Post
    This is correct, if both are not below set value, it will use open throttle ve table. That is why I like to use trimalyzer to tune VE, you can just set a filter for idle flag false, then go back and change to idle flag true, and tune the idle VE
    Trimalyzer? Link?

  6. #6
    Fuel Injected! ralmo94's Avatar
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    Quote Originally Posted by Dieselsj View Post
    Trimalyzer? Link?
    https://ecmhack.com/trimalyzer/

    Website from member on here steavo,
    He created trimalyzer
    No need to re-invent the wheel. But we can make it better

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