infinity i30 drains battery???

my infinity wouldn't start, checked the battery it was totally dischaged & almost no water. Further checking proved three cells are dead. Changed batteries with my Ram, it sucked the life out of my Ram battery as well, and killed it dead! Now I need two batteries, and want to know if anyone has an idea what the infinity problem could be? What do know, is that when i took it for a long drive to charge the battery...it would not kick into high gear and the lights kept flickering, like it was starving for juice. But the alternator did keep the car running once it was jumped?????????? My multimeter is broken so I don't know if the alternator is sending a charge to the battery, any other way to check?

...My multimeter is broken ...

Buy Amp gauge into u dash, install, 50$, lots work? Why not invest instead into new multimeter 10$...

Quite probably your alt regulator is shot, voltage over boiling point 14.8V or 14.5V which is between nissan stupido standard (13.8-14.7V). Some alt info: http://www.cardomain.com/ride/748507/21

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