@ken5124 Exactly what I had: no load idle would randomly drop but recover. It's good to eliminate any possible vac leaks, but that may not be it.
Go into 'afr closed loop' then scroll down to idle fuel learn rate. Turn this down to 2-3.
Then scroll up to 'idle trim jump' both pos and neg. Write down what they are, then try setting them at 10~15. Write down your AFR loop speed, and then cut it in half. Remember to 'send' each change after you edit the value by pushing the button. Then go to 'idle trim rate' and write them down too - but then lower them to about half the default. The POS value should be higher than the neg by 10-30% (based on my playing).
Then go to idle control. Look at the Loop rate up/down. Lower your 'down' setting to very low. 1/2 to 1/4 the default value.
Doing all this should have immediate effect on your idle quality. I did this while idling in the garage. It went from a choppy 600~1100 idle that sounded like it wanted to die on the low end, to a solid 850 and varies by less than +-75.