I thought there was a TSB on the ECM. You're the second '15 4runner I know of that had the ECM replaced. Going to keep my eyes open on this one.
Thanks for the update.
I have a 2010 limited that took an extra couple seconds to start earlier then it idled low. Stopped by Walgreens and it did it again when I left, but this time it died and won't start at all now. Everything is turning over, just not firing. Any experience with this?