I just stopped by the shop that is working on my '84 1.9L WBX this weekend.
The tech showed me the cap and rotor (both Beru) that were really munged up
for being only a year or two old.  Indeed, worst I have ever seen, and the
contact for the #3 cylinder was in worst shape than the others.  This
explains erratic performance where sometimes van would feel underpowered.

In any case, I remember something about if the cap is heavily
carbon-tracked, it means that the high tension wires and the ignition
control module may have been damaged.  Is this true?

John Lauterbach
'84 7-passenger
Macon, GA