Since my meter has duty cycle (I bought a new one just for this purpose) I never tried reading it in just volts. Perhaps there is a forumla you can apply to the voltage readings you took? Someone will know if this can be done.

You can also set the mixture reading the eha current, reading milliamps. Have heard its a more accurate representation of mixture also.

Pin 2 is the ground of the x11/3 port.

__________________
'90 300SE 298k
-300K and it gets put into retirement.
'80 300D 255k Purchased new by family in 1980.

Had a:
1973 220 (gas)
1980 300SD
1992 400E