Talk:Fitting a Crankshaft Ignition Sensor/@comment-82.14.208.254-20150704221343

Checking the sensor's resistance variation when heat stressed will give a good measure of the item's condition. if it varies from the 530 ohms by more than 10% when heated with a hair dryer then the unit is likely to cause eratic sparking. dead items will go high resistant with temperatures up to 80 degrees c. I have fitted my latest sensor on an insulated base on the premise that the metal base is hotter than the engine oil - an experiment that I hope will produce no results......

Poor starting is also possibly a symptom of a failing ignitor. The unit shares a 12v feed to the coil positive and a falling voltage at this point can be rectified by a manual intervention with an additional 12v switched feed or replacement of the ignitor. (subject to diagnosis)

Changing the subject - coil failures are probably exascerbated by exposure to heat (missing engine cover plates) and poor HT connections causing arcing and heat buildup. - Check all HT connections vigourously looking in particular for discoloration of terminals as a possible sign of arcing. leaving the ignition on whilst engine is not running is also possibly exaserbating as current flow through the coils is continuously applied rather than subject to the proportional switching of the ignitor.