I will make it short (ha ha). Erratically the electrical power goes dead. Not just the headlight, but gauges, turn signals, warning... the full monty!

I have an upgraded 60amp Alt, an Optima battery, and a std 1972 240z

The alternator is good, I converted my car to FI and I am able to read my ECU on a laptop with an USB connection and it gives consistent 13,5 - 14 amp all the time, even when all is dead. The ECU and fuel pump is on a separate loom coming from the battery, so the car still run when the old system is acting funny!

You've got proper ground (bare metal) and solid terminal connections?

I think so as the FI is working fine direct from the battery?

Is there an other ground to check beside the main one?

Hmmm, it's mostly when I put the lights on that ALL goes dead

Look for a loose connection either at the fuseable link connection by the starter, the amp meter, or the main fuse box. It sounds like you have a high resistance connection somewhere that is restricting the current when you apply a heavy load.

It might be a failing fuseable link, but I am not sure it they can fail in this way without burning through. In any event, I would try to find this quickly because a loose connection is likely arcing, and that will eventually cause a fire.

Time will tell... but after a slow check of everything... I found a 4/5 broken connector at the alternator. Invisible if you don't have the nose on it

I don't believe in cursing and voodoo:finger: but now that I have fixed my electrical system, the tank is leaking :disappoin

Tell me, how does it feel to have a normal life?

Tell me, how does it feel to have a normal life?

Most of us wouldn't know. We own Datsuns.