Alright well I purchased a battery charger (a DieHard automatic battery charger) and I used it on my Optima. It said that it charged it to 12 volts, so I figured it was good enough to start my WRX. Well it did provide enough juice to use my accessories, but it would not start the motor on the vehicle. I hooked up jumper cables off of my Xterra again, and it started, and it ran at about 1500RPMS for a minute, but then it got down to about 1000RPM and started to idle very rough.
So the battery is at 12 volts, shouldn't the alternator be able to charge it and I shouldnt have any problems at this point?
Any further suggestions?