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Logging LTFT

757 Views 3 Replies 4 Participants Last post by  mememe123
I don't have my wideband setup yet but I do have efilive. What would be best to log LTFT against to gauge rich or lean? Every time I look at scammer its negative which means it's rich but I want to setup a graph plot to see everywhere
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LTFT vs Mass Airflow (Hz)

Copy the labels from the Mass Airflow table and put them in your graph.
just remember LTFT is average for a group or area of fueling not cell by cell, if u want closer i usually use STFT as they are immediate cell by cell, STFT only will also stay close they always stay around stoich without the LTFT help ie if error is say 20% they dont cycle down to 20% and back they will add in 20% and cycle within couple % of stoich
Create custom/user math in VCM Scanner
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if something is red, make sure you add it in the channels.

Closed Loop filters for the graph (use your MAF Freq)
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[2517.161.avg(1500)]=0 and [2517.161.avg(-200)]=0 and (abs([50090.156.slope(2500)])+abs([50090.156.slope(-500)]))<2 and ([6310]=9 OR [6310]=14 OR [6310]=15)=0 AND [6215.242]<140 AND [6215.242]>68 AND [2146.242]>200 and [50010.242]>187 AND [50011.242]<104 AND [2128.242]<104

Look in your HPT tune file Engine/fuel/Injector Flow rate modifier vs IAT (ECM12319) and note what temperature your numbers start changing from 1.000 to something else, in my case 104 degrees and up it starts adding fuel, this will be the number you put into 50011.242 and 2128.242 to filter out the extra fuel.
Same with injector tip temperature (ECM12303) - 6215.242 in filter.

Depending on the engine setup, I would adjust CL to ~6600 HZ. 6750 HZ and up would be PE (once you add wideband O2, you'll know where your switchover is at).
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