The waveform image below, was taken from a petrol engine vehicle, which was suffering from a lack of power, caused by low fuel supply pressure. It illustrates the effects on the ignition ‘spark line’, when loaded. This is a twin static or ‘wasted spark’ coil system.
This waveform image is of the same type of ‘wasted spark’ or ‘DIS’ ignition system, as in the above. Only this is a good sample taken with the engine idling. No faults.
Mark Stammers Diagnostics 