91 honda civic dx suddenly dies while running. I have to hold the key on far right start position to keep the car started. I let off the key and the car dies. Turn the key to the where the starter turns on and hold it there and the car stays running./ Any ideas what this could be?

Replace the ignition switch and harness:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-2.html#post224652

Easy job.