88 xr6 won't start

Yesterday I had a young guy stopped at the front of my driveway. His car had died. We pushed it out of the road. I know that the car doesn't have spark at the plugs or the coil (grounded the plug on the engine, held the coil wire close to the engine). When I check for spark at the plug I did see a short puff of smoke come out of the spark plug hole so I think that the belts are are fine. Cranks fine. He replaced the rotor and I cleaned the distributor cap terminals. I work on my vehicles all the time but I haven't worked on any Subaru's. What should I look at next? He lives about 25miles or so away from here and I want to help him out if possible. Car only has about 88,000 miles on it. Everything appears to be original on it.
He did tell me that he had a starting issue a couple of times before this. It would start and run rough then clear up and run fine.