84 VANAGON manual trans inline motor/Digifant engine management.

Recently I have had an issue with my idle sometimes being too low at
unpredictable times letting the van die during traffic pauses, etc.  I
found a spare idle air  control valve in my spares, but it is slightly
different from the one I have now, so I douched the one that's here on the
van, as well as  Checking connections and vacuum leaks. All that and still
low idle, but not consistently low, just sometimes.

  The Bentley book led me to a screw (imagine, something mechanical!).
Similar to what was used on vehicles with carbs in the old days, this
screw, with locknut, I turned it about 1/3 of a turn and that brought the
idle back into spec.  The van runs right again without the annoying dying
at idle.
   I guess I'll be told now that I can't fix it that way...but I did first
try all the fiddley little resistance readings and test protocols with no
results first, just like s good little automotive technician should in our
modern modular World.

   An aside:  This last tank of fuel again gave me over 26 miles per gallon
in rural driving.  The Fuelly App I've recently began using to track my
driving expenses has me at $.13/mile for the Vanagon, or 24.2 mpg over the
past 6000 miles from my late fall's travels. I'll guess this kind of gas
mileage surpasses most other much more expensive engine conversions, or
even brand new Gucci G.W. style $5k rebuilt wbx motors.