Anyone understand how this works, or if this channel is even valid?
I never paid much attention to it, but noticed recently that my ETC Effective Area was drifting negative during long idle periods. So, I added a few more channels and took a log.
What I'm seeing doesn't make much sense. The log attached picks up after a long idle, then a small blip of the pedal. I see Idle Adapt settling at -1.25 lb/min, which compared to my total air consumption at idle of 0.84 lb/min, is pretty giant. After the throttle blip, Idle Adapt goes nearly zero, but slowly trends back to -1.25 lb/min.
Here's the real question, what is it actually changing? I can't find any evidence that Idle Adapt is doing anything. ETC angle is very stable, and there isn't really anything else that could change the amount of idle airflow.
ETC Effective Area follows the same trend, returning to a reasonable value after the blip, then trending towards an unrealistic number. I was under the impression that Effective Area was derived from physical signals like MAF and RPM, but this suggests something else.
IDK if I was doing it correctly, but I noticed that if I used that PID on my 13gt to modify the idle airflow table that the STIT would be closer to 0. I forget what exactly the process I had for it was, but that seemed to work. I only really needed to do that when I was using the 90mm FRPP throttle body because I guessed at the data for it since none exists. But the car drove excellent when I was finished.
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