[Dangerous Doug]

Could be the coil. I've had two coils fail intermittenty. Once they heat up and expand they either go to an open circuit or short out. Once they cool you can fire it back up again---only to have it die.

Get your DMM out and go for a drive. When it dies, coast to the side of the road and check the voltage at the coil posts. I'm willing to bet you'll find the + and - sides at the same voltage.

DD