Yup. That's why you're supposed to do the idle relearn after you get your timing advanced.

 

My MAF/idle situation is pretty well custom to all that is custom due to all the little things I've done.


My issue was, on a normal day, I was able to change the base timing and leave it as is. On this one day, it wouldn't take once I got out of that screen, the idle cahnged and the timing was back to w/e it was prior.

reason being, my idle that day (too little fuel addition) caused my idle to fall below the threshold I was supposed to be at, and canceled the timing to stick, as the idle was out of tolerance, as we all know, the idle must be within spec as well as the ECT. IAVL/idle/BTDC wont take unless those parameters are met.

After a few points of fuel correction, it was fine, and stuck, without needing to do the idle relearn.