[Sevnson71]

Could also be a wire short. If you replaced everything else that's the only thing I could think of. Something is drawing more than it should. If you have done any recent upgrades or repairs start there. Beyond that you are kinda chasing gremlins by the sound of it. Good luck.

 

[Sevnson71]

Just an update: The car and alternator have been working perfectly since that day. And nothing has changed since. Soooo it’s beyond me what was wrong. On the bright side I didn’t have to buy a sketchy aftermarket PCM

Sounds like the connection was loose. I'd also suggest a little dielectric grease on the pins to protect against corrosion.