93 1.8l Summit will not start

Here's the problem, I blew the head gasket and water pump on this car. I've replaced timing belt,head gasket, pump. Started and timed and ran for 1hr with no problems. Problem today I drove it for a few minutes and shut it off and it wont start? Cranks fine but no power to dist? Checked all electrical connections and all are tight. No blown fuses and timing is correct as far as I can see. Could it be the Computer or Emissions Control Module ? If so where are these located and how to check them?
Is there a way to check codes stored on computer?