Answer:
Both A and B are correct.
Explanation:
The crankshaft sensor is attached to the crankshaft pulley on the
back side of the crankshaft. It is used to pass a signal to the PCM
which controls the ignition of an engine. This sensor helps in providing some basic timing for the signal. If there is a faulty sensor present, the signal will not be received by the PCM. So, it will affect the engine while starting. One reason can be a defective
assembly of the coil.
If there is a faulty [tex]\mathrm{PCM}[/tex], the signal will not be received properly. This will not allow the passing of signals to the ignition system. This will cause a misfire. One of the most common causes of
misfire is a faulty ignition coil. This will affect the working of a
sensor. So, prevent engine from starting.