Recently I posted asking about my sticky throttle cable (this was on an
inline four VW install, similar to the diesel vangon set-up.

  I found the throttle cable, where it goes around the plastic guide "cam"
on the throttle body shaft, that cable had a couple of "fish hooks" (that's
what we called em on sailboat halyards, anyhow)...broken strands...that were
probably catching as I started the throttle cable moving (pushed down on the
pedal).. "Tip-in" is what someone called that part of throttle opening..

  Now it just happens that a mountain bike brake cable is very similar...the
end is compatable and the cable itself is about the same..So I removed that
gnarly rear section of cable and replaced it with a spare mt bike brake
cable, cut to the proper length and clamped in, like the other one....Now is
nice and smooth when 'plonking around' just above idle or when I lift off,
then re-apply the gas...no more "head-snapping accelerations"....(I
exaggerated with that last...)

  Don Hanson