I put my new motor and trans back in the car in May. Ever since then I've been chasing the same gremlin. The alternator only seems to charge when it feels like it. I've changed it twice. The volt light on the dash wasn't working so I pulled the digital dash apart, cleaned all the connections and checked all the bulbs. Put it back together and everything seemed fine. I even took the car to BPG Columbus and it behaved itself. Got home and within a week it's doing the same thing again. I never get a voltage light on the dash but my scanmaster tells me when the system voltage is down. It's always at 13 or higher when it's charging and at 12 and less when it isn't. I can't find anything wrong with it. The grounds check out and I have continuity to the volts light. I put a tester on the 4 prongs on the back of the alternator and none of them are putting out any power so of course there isn't going to be a voltage light, yet it isn't charging. I'm stumped.