[Trackrash]

I was having this issue. There were three causes, at different times in my case.

A bad connection in one of those electrical connectors that goes from the ignition switch through to the frunk. I could reach under and hit the plug and it would spring back to life. Major clue was most all the electrical would go down when this occurred.

A bad, ie intermittent, CDI unit. Once when my car died a friend of mine goes " here's your problem" and hits my CDI unit with a screwdriver handle. Instant whine and starts right up.

A bad fuse to the CDI. When checking fuses pull them out and look at then ends not just the center wire, AHIK.

Don't you hate intermittent electrical problems.