Had your exact same problem twice. I agree with above and I had a bad condenser once. It killed the engine period. First time...start up fine and such but missed only on bottom end. Found the rubber vacuum hose to the vacuum canister was split. Second time....darn exact thing. Well, I had added a ballast resistor due to someone chopping the resistance wire to ignition. Must have missed a lug crimp somehow (it was also soldered) on the downstream side of the resistor. Missed then quit and there it was, no connection. Wire hanging in air. Easy to spot though.
