I've been seeing an intermittent low idle-sometime no idle with my Digifant
84 van 92 rabbit/fox/Jetta ecu, etc.  This condition is occasional, when
not happening, the engine behaves normally, my fuel consumption
has not changed.
  My normal idle is about 900 rpm.  Recently I have had the idle decide to
run at around 400 rpm...it seems to be smooth, but 400 rpm is too low and
now the motor sometimes dies down there.  When I cycle the key and re
start, it will again run at the low idle...no "reset"... I have a new temp
II sensor and new plugs...the old plugs read normal.  My idle control
thingy hums as normal and I have no obvious new vacuum leaks. Multiple
different fuel sources.  Throttle switch seems to conform to the Bentley,
though I have so far only  check ed the mechanical, I have not run any
electronic diagnosis yet.
  Anyone want to suggest the most likely cause to this sometimes dying of
my Digifant inline? Tia, Don Hanson