You can usually check a crank sensor with a multimeter.
Find the plug, disconnect it and measure the resistance between the pins.
It should be under 1000 Ohms or so, if it is higher it is faulty.
The heat cycles of the engine cause the windings to break down over time giving poor output signal.
Sometimes they can cause the car to cut out when hot, other times they can prevent it from firing when cold but once running it will be fine.
I played 'Hunt the crank sensor' with my son this evening..... (not a five minute job is it...?)
I found the brown connector first and followed it through to some obscure cobweb filled orifice behind the engine, the starter motor and below the inlet manifold. Some of the topics suggest that small hands are needed. I would like to change that suggestion to 'small hands with three fingers removed'....
Before attempting to remove the sensor I checked the resistance and found it to be 840 Ohms. My new sensor that came with the car also checked out to be of about he same resistance, so after considering whether or not to carry on, I decided that since I have a new one I may as well carry on and fit it. With car on ramps I then decided to drop the exhaust. That gave me marginally more room, but not much. I managed to get the 6mm Allen screw out, but I just cannot remove the sensor! What do I have to do?
I have also realised that the new sensor has the cable entry and the securing hole 180 degrees apart. However, the original one stuck on the car has the cable entry at 90 degrees to the fixing hole, so even if I could get the damned thing out, the current new one probably wouldn't fit.
I've given up for tonight. If the above wasn't bad enough, the car, which is outside, was then too high for the garage door to clear it when closing it, so I've had to drop it back down off the stands that I had carefully put it on to work underneath.
What do you think - leave the sensor or change it, and if I should change it, how do I get it out?