The airflow potentiometer is supposed to 0.85v +- 0.1v so not sure where you got that spec from. Yours is fine.
Engine running is more important than engine off....
Duty cycle is NOT in closed loop at 99% -- that is open loop! Closed loop is an oscillating duty cycle which shows the system has the ability to compensate for change.
Still looking too hard for problems!! Concentrate on the meter tower and adjustment. It may take a good 30mins before you get the right place. The initial turn will cause an increase in % because you are (physically) pressing the plunger allowing more fuel in (hence the momentary change). If its
heading in the right direction away from 99%, then keep doing it.
eventually it will either find its way to 50% and oscillate around there, or go to 0% in which case you need to go CCW (or vice-versa...some Craftsman DMM's read opposing duty cycles). It may need 1-3 full turns to find the correct height.
Think of the mixture unit as a log see-saw....Your allen key screw is simply changing the middle log so that the height at its maximum extension is higher or lower. The higher the log goes, the more the plunger on the fuel distributor is pushed in, more fuel, and the less it is pushed in, the less fuel. If the see-saw is sitting too
low its not even making contact with the plunger, showing excessively lean mixtures at idle (which I bet is what is happening). Keep turning the screw to raise til the plunger finds its happy level at idle and it might be your golden ticket.
Once you have the duty cycle at or around 45-50% with it increasing no more than 10% at WOT, you have found the correct spot.
As I said in the previous thread though, I know you were fiddling with the fuel distributor, so if you did also the EHA, you need to return it back to its original position or direction.
This is why I don't advocate touching or adjusting
anything but the duty cycle (for future readers/researchers) because if it ended up being something simple, like the vacuum leak, you now have issues returning multiple, fine adjustment units back to where they were originally. It's tough
