I've tried searching here, but haven't found anything like the problem I'm seeing.

About a month ago when I was driving my NA coupe started having problems. A rash of warning lights came on (ESP, battery, BAS/ESP among others.) The car started to stumble, and at one point the automatic would not shift out of first gear. Fortunately I was close to home, and got there before it quit running altogether. I tried to start it, but the starter barely turned over before if finally quit. A was able to jump it and took it to a local shop. They said the alternator was fine, and suggested a new battery. That worked for a while, but a couple weeks later, it happened again. I took it to another shop, who pointed out that the clamp on my negative battery terminal was cracked. The replaced, and again check the charging system. Things seem to be okay for a while. At this point I remembered I had a volt meter to plug into the cigarette lighter, so I decided to pop it in and keep on eye on things. Earlier this week, I was out running a quick errand. I ended up sitting in the car with it idling for about five minutes. When I started to leave, it happened again, warning lights and bogging down. I looked at the volt meter (which had seemed fine on the way over) and it was showing 9 volts. I pulled over and took it out of gear and let it rev to about 2000 RPM. The voltage bounced back up to just over 12, and I made it hope without a problem.

The voltage doesn't seem to drop when the car is parked for an extended period. I almost seems that at some point something starts drawing a large amount of current. Needless to say I'm not feeling comfortable driving the thing. Does any of this sound familiar?