Does a crank sensor cause your car to not start at all?
A faulty crank sensor can absolutely prevent your car from starting at all. The crank sensor tells the engine control module (ECM) the position and speed of the crankshaft. Without this information, the ECM can't trigger the ignition system or fuel injectors, resulting in a no-start condition. It's a common cause of no-start problems, but not the *only* one.