Idk if this helps but my car started doing the same.. everyone that tested it said the alt was good. So a couple more months went by and I noticed I had to drive the car everyday to keep it alive. Well a couple months later the alt was bad, would even keep the car running good unless it was idled up. So i think it may be the alt:crap: just started to give. It seems that with my first alt I blew the regulators and it just started going downhill from there.