Idle Airflow w/ and w/o clutch engaged

[phuz]

100%. But why is idle adapt not kicking in to save the stall?

[SiriusC1024]

Don't be concerned about that until VE is accurate enough to ensure tight fuel trims. If it's still an issue afterward post a log and we'll take a look.

[edcmat-l1]

100%. But why is idle adapt not kicking in to save the stall?

That's not how they work.

[eficalibrator]

You cannot accurately adjust idle airflow (or STIT, LTIT) if the VE/dynair is not correct yet. Otherwise, the ECU is making corrections based on a wrong number. Getting the VE right also helps avoid rich/lean variations that make idle control sketchy. You need to be able to hold stoich even as airflow changes before you can declare a stable min airflow.

I wouldn't want idle airflow to be the primary mechanism preventing stall. Spark trim (underspeed control) should be far more powerful here as long as base idle airflow was in the ballpark (and based on a real number as I said above).

More Training HERE.

[phuz]

You cannot accurately adjust idle airflow (or STIT, LTIT) if the VE/dynair is not correct yet. Otherwise, the ECU is making corrections based on a wrong number. Getting the VE right also helps avoid rich/lean variations that make idle control sketchy. You need to be able to hold stoich even as airflow changes before you can declare a stable min airflow.

I wouldn't want idle airflow to be the primary mechanism preventing stall. Spark trim (underspeed control) should be far more powerful here as long as base idle airflow was in the ballpark (and based on a real number as I said above).

More Training HERE.

Thanks Greg.
I completely agree and I found the primary issue. With the slow rolling speed, it was using the main spark table (not idle table), and when the RPM dipped, the timing dropped significantly making a bad situation worse. The cylinder airmass during that "stall" was almost 0.5g and the timing in that area was 0 degrees (leftover from stock). Yes the airmass was probably higher than it should've been due to excessive VE in that section, which is why it tended to show rich as it stalled. It's taken me a bit to figure out when/where it transitions from main spark to idle and vice versa.