HELP! Randomly no spark!

What color is your control box. factory 72 340's are blue and externally grounded with the green/red wire. The later orange control boxes are internally grounded and that pin is not used. Those old units would fail when hot and start when cooled down. They came on 72 and 73 340 cars. If you have a blue box that may be your culprit. Been there more than once. Its a ground you can't check. Put a 4 pin box on if you have a 5 pin.

Any color will work for a test.


I just thought of this. I must be really old. Who the hell would have a original blue box after 50 years