Tuff to Start

Thanks guys; good catch on how to test this. Wish I could say I was just testing you BUT, truth be known, I thought the normal source to the alternator and ballast was still ON when in START; my 70's/80's Dart mechanic'ing is getting a good brushing up..... The jumper to +12 direct is the way to go. I like the direct voltmeter test on the coil.

And agreed on the symptoms that it can kick over when the key is released; seen this / done this before. But if the ballast bypass switch contact is erratic or dirty, it can fire or not in the START position; this can occur as the key is jiggled in the START position. Similarly, the wire connection for this line in the harness connector can be erratic/dirty/corroded, and produce erratic starting. The voltmeter test can tell this.

Regardless, this should to be checked based on the symptoms. Not an unknown problem.....