During Closed Loop Running, ( Not during Idle ) the Voltage should be Dithering between .2 Volt and about .8 Volt.. this will be Fast Idle, and Smooth Freeway Running.. Not Pulling Anything.. both sides should be cycling at about the same rate .. and never sit at either end when running..
Idling is a completely different game in the Zed.. it will drive you batty trying to get that sorted out..