Car won't start

I have a 1992 honda accord dx. The car will not start. It will turn over but will not crank up. I have replaced the battery and wires connected to the battery, distributor cap, and fuel pump. None of these have remedied the problem any suggestions?

P.S. The car was running fine and thirty minutes later it would not start. The check engine light came onregularly after driving for 15 minutes. But, there was no hesitations or other signals that the car would stop cranking. No hesitation on starting until it would not start at all. All fluids are full and clean.