You could chase your tail for years posting symptoms & getting numerous "answers" here on the board. There's one sure fire way to chase the gremlins away...
Make sure all the mechanicals are sound - do not pass go, do not collect $200, go directly to valves, points, condensor, timing. ONLY THEN start reading through the bible of D-Jet:
http://members.rennlist.com/pbanders/
godspeed bother.
-pt