[alfan]

Thanks a lot, guys, for your helpful posts. Problem solved! The ignition coil tested OK, and the ballast resistor presumably good. Removal of the wire at the fuel cutoff solenoid resulted in an instant start, so must have been the injection pump microswitch. I understand that the microswitch is in a pretty tough location to replace, so I guess for now I will put up with the pop-pop-pop when releasing the gas pedal.

My lesson in this one was to learn that this rather odd problem could have two equally possible causes.