I went through what I thought was a small puddle and the water must have flicked up and covered the dizzy area, misfired for a few mins then went away never to come back so the MOT guy was correct in saying that.
What brand crank sensor did you get? Siemens VDO from ECP was the exact same as the one i removed from my car so could be the original (provided it wasn't replaced already) but 4 years later its still going ok touch wood. Have fitted Meyle, GSF cheap items and had them come back a week later.