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  1. #1
    Fuel Injected!
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    I'll check math function.

    It is SLC2 Free by 14point7
    This is what i found
    0[v]@0.68[Lambda] linear to 5[v]@1.36[Lambda], 10[AFR] linear to 20[AFR] equivalent for gasoline

  2. #2
    Fuel Injected!
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    Okay, then that sucker is incredibly simple. It's a linear equation.

    If you want to display as AFR (Gasoline) instead of Lambda (any fuel), then:

    AFR:1 = N*(10 / 256) + 10

    For example, if N is 128 (~2.5V), then:

    AFR:1 = 128*(10/256) + 10
    AFR:1 = 128*(0.0390625) + 10
    AFR:1 = 5 + 10
    AFR:1 = 15
    15:1 AFR
    1990 Corvette (Manual)
    1994 Corvette (Automatic)
    1995 Corvette (Manual)

  3. #3
    Fuel Injected!
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    I appreciate your help

  4. #4
    Fuel Injected!
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    Can't make MAF work

    A274 GM datastream description

    ALDL MODE 1 MESSAGE 0 DATA LIST
    Word #46
    GP6EAFND GMP6-E NON-DEFAULTED AIRFLOW (MSB)
    I get value 2 at idle
    If I use math function GM/SEC = 512N/65536 then I get 0
    I tried word#47 GP6EAFND+1 GMP6-E NON-DEFAULTED AIRFLOW (LSB)
    ~200 at idle and it decreases when pushing the pedal.

  5. #5

  6. #6
    Fuel Injected!
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    What steveo said. If the MSB of the 16-bit Word is 2 and the LSB of the 16-bit word is 200, then the complete value of the 16-bit word is 712. Plugging 712 into the MAF conversion equation from earlier, it comes out to 5.5625 gm/s at idle. At hot idle my '95 Corvette hovers around 7 gm/s, for comparison.
    1990 Corvette (Manual)
    1994 Corvette (Automatic)
    1995 Corvette (Manual)

  7. #7
    Fuel Injected!
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    Thanx guys, i've already fixed it and it works.I was trying to get data from 1 byte, not 2. Time after time.

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