2000 Dodge Caravan Caravan won't start

For the last several months all the lights on the van including the interior and dash lights "flicker" slightly. Not all the time though. It seemed to get worse when the cooling fan was running. I have cleaned the battery terminals and checked charging voltage. Seems okay at 14.5 volts or so. Today when I checked it again it tested at 12.4 volts. Not enough, I know. I didn't have time to check further and the wife had to get to work. Has luck would have it, it was towed home this evening. It would turn over most of the time and every once in awhile nothing at all. After testing and checking more, I found the two battery cable to power center terminal stud nuts 3-4 turns loose. This would probably explain the "flickering" and the not turning over at all. Do you agree? After tightening the terminal nuts it did start but only stayed running long enough to drain the fuel pressure. I have checked and swapped out the FP relay and checked the ground and power to the pump. All seems fine but the pump won't run. I'm guessing it's bad. My question is: Would running the system with a loose connection as I found at the power center cause the pump to fail or is it just a coincidence?