360 not starting "Now"

It’s a 4 wire ecu. It was a kit added by another person. what is weird, is when I started it for the first time, like I said it ran fine, then after that, it would not run. It would start and shut off (bad BR) found I had forgotten to put the condenser under the bolt, and saw sparks. Replaced BR and put it under the mounting bolt, It worked fine. I will try swapping the ECU and removing the condenser and see what changes.