My guess would be the pickup. I've replaced 3...or 4 (can't remember now) of them in the last several years. They're junk, and they can "check" good, but still be bad. Twice I got stranded from this issue. I now keep a complete spare distributor in the trunk, just in case. It's easier to just swap it out, than to mess with taking the pickup out. But I also carry a spare pickup with the spare distributor. Yeah, they're that bad.