Idle AFR reading (stock)

[IS300E30]

Would a 14.17 - 14.34 be good for stock from factory reading on idle?

If the above range is perfect, what would be the best idle setting within that range, for a completely stock using non-ethanol gas; 14.17, 14.21, 14.23, 14.28, 14.34? If so, why?

[zaq123]

0.85 lambda is as rich as yo want to idle. Otherwise your plugs will be charred

[digger]

closed loop narrow band should idle around 14.5+/- for the cat

[Northern]

Low 14s will often idle better but for catalyst efficiency and because of how the narrowband works it'll target stoich.

[IS300E30]

Per the Bentley book, the CO% should be between 0.4-0.8%, which would equate (per attached screenshot table) to 14.17 - 14.34 AFR.

Am I missing something?

[zaq123]

https://www.hpacademy.com/courses/road-tuning/idle-tuning-idle-mixture/