OK guys this is starting to get annoying. I didnt use my mustang all winter long. I may have started it 2-3 times over the course of 5-6 months. Right off the bat 3 weeks ago when i took the cover off my battery was dead obviously. I replaced the battery but the car wouldnt idle right. It would idle for a second and then just die. If i held the accelerator at 800-900 for a couple minutes to warm it up and it would idle fine for awhile. That night i was at a stop light with my lights,fogs,heat and everything kept going dim and the idle would surge. Battery level would flucuate and it would barely hold itself. That week the following was done to the car BBK Shorty Headers, BBK O/R X-pipe, 65mm Throttle body, Cold Air Intake, New plugs, New Wires, Oil Change/Filter change, Chip from BAMA Performance. Car still has the same idling problem. Now as far as how much load is on the battery from all the electronics i have, is just a subwoofer and the car ran fine before the winter with it in. The question is what could be causing this problem? Could it be a weak alternator? Old fuel? or what?