I had a crankshaft sensor go bad and it would start and run rough.... start and run fine.... crank and crank and not start....

It could also be the CAMshaft sensor.... the ECU use both the crankshaft position sensor and the camshaft position sensor to start.... x number of pulses of one between the pulses of the other. BUT, as stated, it is usually the crankshaft position sensor(CPS).

Make sure you get a good look at your crank pulley and determine if it is going bad. You DO NOT want it flying apart while running..... very bad ju ju