Evening, got home from work to find my new crank shaft sensor awaiting. Gets the trusty tool kit out, locates the sensor on the car, matched the part numbers up and all good, takes the sensor out to find the tiniest bit of rusty fragment stuck to the end of the sensor, the piece must have measured about 1mm by 1mm
so removed it, cleaned up the sensor put it back in and hey presto. She is running like a new car, idles like a purring kitten, starts instantly on turn of the key.
Now my understanding of the sensor is its just a magnet, so im now in the belief that this tiny fragment of metal stuck to the tip of the sensor has been giving false readings and causing my headache. Any info would be appreciated.