I have a 2005 pontiac g6 sedan. The other day I parked the car, quite hot outside, then when I went to start it, no go. It clicked like the battery was dead, but the entire electrical system was restarted, clock set to 1200, radio on, windows worked, lights worked, jumped it and it started. Drove it for 30 miles turned it off when I got home and restarted once, the second time I restarted it, just click again. Again I jumped it and it started. I let it run for a good hour then shut it off. While it was running I disconnected the positive cable and the car continued to run, im my mind eliminating alternator problem. This morning I went outside to start it, turned it to the on position, clock was still set properly, when I turned the ignition the clock reset itself and it wouldn't start. What could be causing this? Perhaps a new battery would help?