You are half right ........ cruising IS closed loop The zed ecu ignores O2 feedback at idle, which makes it OPEN loop. If idle was closed loop, adjusting latency would have little effect on idle mixture because the O2 feedback would constantly try to pull the AFR back to Stoich
This is standard Nistune with Feature Pack showing O2 fuel trimming commencing at 51 degrees. Map trace showing O2 voltage in Closed Loop/idle as well as Open loop. Closed loop can be deactivated which some tuners do.
