Hi Keith,

The failure we are discussing has always happened on the highway, with a
fully warmed engine. Every time.  FWIW, only about half of my commuting
is highway.

I had a coil fail in my baywindow camper on vacation back in 2006... It
felt exactly like the problem I am seeing now. In that case it was a bit
easier to diagnose since the ECU does not control the spark in an
L-Jetronic engine.

Another possibility that came up in P-mail discussion is the ignition
switch; but I did not notice any of the switch-dependent accessories
stutter during these incidents.

Happy Trails,

Greg Potts
1973/74/79 Westfakia "Bob the Tomato"
1987 Wolfsburg Weekender Hardtop
www.busesofthecorn.com
www.pottsfamily.ca

Keith Hughes wrote:
SNIP

> Shorts in the coil
> *usually* start causing problems when Hot, but not always.  Since,
> however, the coil heats and expands as you run the engine (flexing the
> primary/secondary coils in the dielectric oil), you should notice a
> difference in performance (either better or worse) the longer the engine
> runs.