My dodge ram 74 one day while driving just cut out with no warning, and when you try to start it, it is extremely hard to start. Sometimes you have to wait a while before it starts backup. The engine cranks but doesnt fire. When it does start it drives for about 5mins(well it has its mind of its own), the engine just cuts out, I dont think its a fuel problem, but a electrical problem. Ive since changed the distributor cap, rotor,coil, spark plugs, igntion leads. Any ideas on this problem would be really appreciated! Thanks