My cars engine will turn over but not fire up every time...?

I own a 1990 Plymouth Sundance, car is my daily driver and just surped 321,000 miles. I have driven the car 1000 miles since i put the cyclinder head back together. I chose good parts like Mopar Performance head gasket, head bolts, re-did all vace hoses and the list goes on. I pulled out a spark plug and left it hooked up to a plug wire and cranked the motor to see if i had spark and i do, car started up fine....but sometimes when i go to start it, won't fire up until after the 4th attempt!!! Pick up coil seems to be ok, ignition coil is good, plug wires good...so i dunno whats going on