I was beginning to think about what you said and maybe my battery is just on it's way out or needs to be fully charged. At this point it's probably about a 3-4 year old battery, but it still seems like the battery should last longer than that, but it's been a good while since the battery had been in a running car and I've never actually charged it.

A few other things I came across. The inhibitor wire that goes to the ECU I had removed, but I keep coming across posts saying to ground it, and I think I need to plug the ZXTs Fuel Pump Modulator into the harness. I don't know if that will make a difference, but I had that still connected back when I was running the Z31 setup on my 280ZXT. I figure I'll get that hooked up, either charge the battery up all the way or throw a new one in there, and if still no luck, I'll just start going through the entire EFEC section of the Z31 FSM to test the ECU and it's components.