While trying to trace the source of an intermittent cutting-off of my 85
1.9 waterboxer, I have come across an unusual source for this problem.  I
think of this as the Nearly-Empty-Bottle-Of-Ketchup source of an
intermittent running problem.  In my rig, the coil is nestled on the left
firewall, squarely facing the front of the vehicle, and under the "High
Voltage" double relay black box.  The primary coil wire is forward facing on
a level plane perpendicular to normal gravitational force.  Have had a
recent problem where when I sometimes hit a small bump, my engine would
cut-off.   I would then open up the engine compartment, jiggle a few wires
and be on my way, again. I naturally wondered, hey, what's the skinny!
Yesterday, my jiggling finally paid off.  I was able to narrow my pursuit
down to the primary coil wire from the coil to the centre of the
distributor.  It turned-out that the problem was related to the natural
slamming of the rear hatch, whereas the primary coil wire was being jolted
out of contact by the slamming action of the hatch, and it's forward facing
position.  Kinda like what you do when trying to get that last slug of
ketchup from the bottom ot the bottle, whacking the bottom of the ketchup
bottle with the palm of your hand.  Because of the horizontal forward facing
position of the coil, every time I slammed the rear hatch (bottom of the
ketchup bottle, so to speak)  the coil wire was being slowly nudged forward
with co-operation from the silent action of Newton's Third Law.    Should I
blame Newton for this?  David