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Thread: Ls7 hot restart goes lean

  1. #1
    Tuner in Training
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    Ls7 hot restart goes lean

    Want to see if this is normal or if any of you guys have seen this. I've got an 08 z06 fully built h/C/I. Cam is a btr stage 3. The car runs and drives very well as I've tuned it myself. Maf curve and VVE are all -2-4%. Whenever I shut the car off and restart it, as soon as closed loop turns on it pulls fuel until the wideband is showing 1.3 lambda or leaner. The engine changes pitch so it's definitely going lean. Does that for a few seconds then settles back down to 1. It's not really an issue just curious to find out why it does this

  2. #2
    Senior Tuner
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    Probs running a test. Which version of hp are you running?

  3. #3
    Tuner in Training
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    The latest version 4.8 I believe don't have my laptop in front of me to confirm

  4. #4
    Senior Tuner
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    if u have zeroed out the ITT offset then that is prob your issue

  5. #5
    Tuner in Training
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    It's not zeroed out. I've tuned that table as well. Or at least I think I have. If I command open loop my actual lambda matches what's being commanded exactly all the way through Injector tip temp showing 170 degrees. That's as high as I've seen it go when heat soaked

  6. #6
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    Cat test and O2 tests still in play?

  7. #7
    Tuner in Training
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    I'm catless so cat test is definitely off. Not sure about other o2 tests?

  8. #8
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  9. #9
    Tuner in Training
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    Ok I forgot about that one. They are both disabled

  10. #10
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    Try increasing your readiness delay to 60 seconds.

    Screenshot 2022-08-06 131900.png

  11. #11
    Tuner in Training
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    I'll try it report back. Thanks!

  12. #12
    Tuner in Training
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    I made the changes above to the o2 readiness table and the car likes it! Doesn't go lean anymore and reported tracks commanded eq perfectly. Thanks hjtrbo for the input! Much appreciated