Idle fuel mixtures while using flex fuel

[Grant Smith]

Ok so from my understanding, on my type 3 ka24de 53f0F ecu. Assuming TP min is underneath the idle load, the way to control fuel mixtures at idle is k constant, TIM, and latency. From my understanding there is no o2 sensor feedback at idle. So the idle mixtures cannot he controlled by the fuel cell map? So my question is how is a proper idle mixture maintained while using flex fuel? Won’t the mixture lean out as more ethonal is added to the system from the baseline where the idle mixture was set? Does the ethonal fuel table compensate for this somehow?

[Grant Smith]

The only way I could see this system working properly is if the ethanol content table is a lookup offset for the TIM instead of an offset over the main fuel map

[Matt]

Fuel map is always accessed, even at idle. See page 11 as this is part of the fuel calcs
https://www.nistune.com/docs/Workshop%2 ... %20Web.pdf

Also the AF trims are always accessed, but where/when they adjusted depends on settings. Normally they are adjusted in closed loop areas (where the O2 feedback flags are defined, but also within closed loop load/RPM parameters)

I don't think they are adjusted at idle from memory with this car. If you adjust the fuel cells, you will see if the STFT/LTFT are affected at all (and this in turn alters the injection time)