Distributor Pickup test

There is no possible way, without expensive test equipment, to "truly" test such things "for certain." Without specific engineering data on the component such as inductance, etc, even that might not be practical, possible, or of much accuracy--especially with questional quality and specs of import parts!!!

In other words, try a replacement. and THAT is coming from a guy who hates to "throw money and parts" at a problem

An example is something that would cause an internal partial short. IE a few turns of the coil have corroded, somehow been overheated by current that is not supposed to be there, or had some defect in the wire when new.........some way that turns of wire are shorted.

You might think this would not make much difference, but what happens is, that these shorted turns make what is called "a shorted turn" or "shorted winding" and this acts sort of like in a transformer and degrades the performance of the coil It just won't generate the pulse power that is needed. This same fault applies to other components--the rotor of alternators, or either the primary or secondary of an ignition coil.