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Thread: Timing Oscillation in boosted 5.0

  1. #1
    Advanced Tuner VodeAn's Avatar
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    Timing Oscillation in boosted 5.0

    I see KR adding and removing a couple degrees, but any idea what might be causing the small variation? What should I log to narrow this down? Spark source or something like that?

    Attachment 71200

  2. #2
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    Different mapped points being used with a good bit different timing in each one could make it more noticeable. Load moving up and down also. I wouldn't worry to much about it as long as there are no major dips. Post the actual log if you want me to look a little more.

  3. #3
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    Looks like ECM added timing, hit some preignition, so KR went back to 0*, then it added more, wash rinse and repeat. Remember that going from -2* of KR to 0*KR means the ECM ran into some premonition so it had to pull the timing. Thats just the knock system doing it's job. 0* of KR when you were -2* of Kr doesn't mean you have 0 KR, it means the ECM had to reatrd timing 2* of timing so ECM stopped adding 2*, which left you at 0* of KR adjustment over all.

    Hope that makes sense

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    0 demanded brake torque, fluctuations in mph. Makes me think traction control.

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    I thought he was asking about why the wavy line for spark instead of it just stair stepping right along with the knock sensor feedback but instead going slightly up and down all the time.

  6. #6
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    log all sources and mapped points. Then post the .hpl log so there's more info to go on.

  7. #7
    Advanced Tuner VodeAn's Avatar
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    Quote Originally Posted by ridenrunwv View Post
    I thought he was asking about why the wavy line for spark instead of it just stair stepping right along with the knock sensor feedback but instead going slightly up and down all the time.
    Correct, I'm going to look into the mapped points and torque sources.
    If I still have issues I'll post up a log.

    To the other people suggesting I look at KR I appreciate you trying to help but did you even read my original post? I am well aware KR is adding and removing timing and was asking about the smaller delta.