Tuning "?", more like definitions
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Tuning "?", more like definitions Ok, Understand Torque Management, and COT, and even the Low vs. High Octane tables.
But what is LTFT's info, how does it relate to tuning issues?
Also, what A/F ratio does 940mv (left side) 950mv (right side)equal. and which way is leaner, smaller mv # right?
TIA. Charlie.
But what is LTFT's info, how does it relate to tuning issues?
Also, what A/F ratio does 940mv (left side) 950mv (right side)equal. and which way is leaner, smaller mv # right?
TIA. Charlie.
Re: Tuning LTFT = Long Term Fuel Trims, make them -8 at part throttle (18%tps.) Leaner is smaller mV. That's a good reading but it really can't be related to an AFR unless you are using a Wideband O2.
Re: Tuning LTFTs are an average of STFTs (short term) they are the value of correction the PCM is making to keep you at a constant 14.6 A/F.
If the values are (+) then it is adding fuel to correct a lean condition and vise versa.
If you go WOT while the LTFT value is (+) the PCM automatically assumes you will be lean and will add a predetermined amount of fuel (based on the LTFT value) above and beyond what the PE table calls for.
If they are (-) no fuel will be added, taking one less variable out of your tuning.
If the values are (+) then it is adding fuel to correct a lean condition and vise versa.
If you go WOT while the LTFT value is (+) the PCM automatically assumes you will be lean and will add a predetermined amount of fuel (based on the LTFT value) above and beyond what the PE table calls for.
If they are (-) no fuel will be added, taking one less variable out of your tuning.
