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Thread: Erratic spark advance under acceleration

  1. #1
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    Default Erratic spark advance under acceleration

    I've been data logging recently and noticed some hesitation under acceleration most noticeably in fourth between 3000 and 4000 rpm, MAP > 95kPa. I thought maybe a spark plug misfire, no codes.

    I found it in the log and spark advance is very erratic, I was logging retard due to knock which showed none, ill log total knock retard next time to see if its burst knock, I do have spark smoothing disabled also.
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  2. #2
    Joe (Moderator) joecar's Avatar
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    Log the EST_ pids to see what is pulling spark... if you can reproduce this.

  3. #3
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    did you find out what it was?

  4. #4
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    Quote Originally Posted by dian View Post
    did you find out what it was?
    Yes, burst knock retard, I zeroed the table and it went away

  5. #5
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    really? how so? isnt bust retard from fast pedal movement? you were at wot when it was happening, no?

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