Help with MAF calibration
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Help with MAF calibration
I've been reading a lot about tuning and trying to figure this stuff out so please be patient. I understand about how to tune with the LTFTs and STFTs when in SD. What I don't understand is when the MAF is plugged back in, how do I dial it in to match my fuel trims. What I've read seems to be mostly between people who already know what they are doing. I'm trying to figure this out but need a helping hand. Thanks for any help.
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I don't think that my laptop has excell because I just bought it to learn to tune with. How do I figure the relation between scanned MAF frequency and fuel trims?
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You will want to set up a histogram with MAF freq vs LTFT. Once you setup the Histogram you will go ahead and scale the MAF. If you have positive LTFT then you will want to add the the MAF table (in the correct hetz) if you have negative LTFT then you will want to subtract from the MAF table.
Now in example say that bewteen 2500-3500 hz you notice your LTFT are around -14, then you will want to subtract 7% from those cells in the table. Or you could multiply it by .93.
I use a small spreadsheet i created that takes half of that value and adds/subtracts it against my actual value from the tuner. Copy paste copy paste, it can be done the by hand but takes a while.
Now in example say that bewteen 2500-3500 hz you notice your LTFT are around -14, then you will want to subtract 7% from those cells in the table. Or you could multiply it by .93.
I use a small spreadsheet i created that takes half of that value and adds/subtracts it against my actual value from the tuner. Copy paste copy paste, it can be done the by hand but takes a while.
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Thanks guys. I set up a histogram that has the LTFTs percentage vs. the MAF hz. The hz being on top. So when we log this I'll need to take the percentage and work with it as described above?
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Add the stft to the ltft in you histogram. The just multipy by that %. I have a fiter that only allows the cell to update if the commanded fuel rate is greater than 14.2. You do have a wide band? If not get one. I also have a histogram that updates with the commanded a/f is less than 13.5. It it the wide band error.