Timing belt?? If there is a section of the timing belt with no teeth on it, it might be turning till it get to that point, slipping causing it to turn over fast, grabbing enough to turn over normal, but would not be able to start because it is now out of time.
THE netural Saftey Switch could B bad .
It could be the starter solenoid
A bendix.
No way we can tell from here. If the engine cranks, it is not the battery. The battery can be good and the engine not crank due to other problems. Sorry, but we really cannot diagnose by remote control.
Stuck relay or the starter is wired incorrectly.
1989 ford F250 Fuel Problems, It cranks but wont start
Fuel? spark?
I say try changing out the crankshaft sensor.
if its cranking but not starting most likely fuel pump
i would say you have an injector problem. usually a cloged one can cause that.
could be the starter or the solenoid, they arer pron to heating up especially when using headers, peace
could be disdributor
try changing your fuel filter, sometimes if it gets clogged the fuel pressure drops to zero causing the engine to stall, when you are cranking I assume you are also pumping the gas (repressurizing the line)
Replace the engine coolant temp sensor.
Some possible problems when your vehicle cranks, but won't start are a bad crankshaft position sensor, or a faulty ignition switch. Another possibility is a loose or broken wire that runs from the sensor to the PCM.
common problem is the ignition module or coil pack, there were several problems like this reported and changing the coil pack fixed these problems
it is easier to pedal with longer cranks because you have more leverage but it is not necessarily better to have really long cranks.