FiTech EFI system

SalC said

It's no longer backed out that far, when is was it idled fine as long as the engine was warmed up. When is was cold it was hard starting and would barely idle but the IAC count was ~10.

Now I have it set where the IAC hovers from 0-4 but it idles much better and starts fine. The idle is a bit faster upon startup and when I take it out of gear but after 15-20 seconds drops back down to normal. Is it ok with the IAC that low?

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I didn't like the idle at first either with the computer in full control, I had to turn down the learning.
What I noticed was the learn value for the fuel and IAC was jumping all over at idle. I reset my idle learn values under idle control. Then I turned down the "Idle fuel Learn rate" under 'AFR closed loop' menu. I put it down around 10. Then I set my loop up/down into the teens range (15 or so) and let the idle fuel stabilize a bit. I watched under the dashboard for the fuel learn number. Once it seemed to settle a bit, I turned the learn rate down to ~5 and upped the loop up/down on the idle back into the 20's. It got FAR more stable very fast.

Do this with the engine warmed up first, if you want to try it. Then let it idle a bit. I also played with the idle trim rates a bit in the closed loop AFR menu. These will be very different for every engine setup. Basically I just ran them way low, then way high and took notes, and zeroed in on what seemed to help most. The result was no longer seeing my IAC steps swing wildly from 0 to 20 and back while the AFR bounced from 9 to 15 and back. Now it idles with the AFR within .5 at the extremes, and the idle step will vary every 2~3 seconds instead of constantly.

I suggest watching the dashboard and data logging whenever you can. It really helps to watch the controls (fuel trims, IAC counts, AFR, etc) to see where extra work is needed to help speed up the 'self learning'.