S14 Alternator only charges when you rev
 

Hey, I have a '97 240sx with a KA-T that is having some charging issues. Sometimes when I start the car, it idles at about 900-1000 and the voltage is at 14.3v and everything is fine, however if I go for a drive it'll start acting up.

Other times when I start the car the idle is low, closer to 550-650, and the voltage at idle is about 12.6v. When this happens, at idle and under load (blower motor, headlights and hazards) the voltage will drop down to 11.2v-11.5v. If apply some throttle and increase the rpms then the voltage increases sufficiently back to about 13.8v-14.3v at about 2000 rpms both under load and not under load.

The battery is relocated to the trunk and the car is on an AEM Infinity 5 ECU with a custom wiring harness.

I've changed the battery, checked belt tension, changed the alternator, and checked the connections at the alternator, checked the fuses. The problem is still persistent. I have a data log from my ECU if that helps, I can upload it.