Replaced 1 crank and 2 cam shaft position sensors..also put new fuel pump..now since prior work car stalled and continue having problems starting.throwing code P0335 crank positioning sensor a circuit..What is it??

 

Welcome, but since you haven't posted any other info on your Z (mileage, mods, past issues) it's hard to say. Since you've thrown a bunch of parts at it, I suggest you take it to a qualified Nissan tech in your area to get a complete diagnostic and repair. Better than having us guess from behind a keyboard.