I'd noticed the instrument panel does a strange thing when you open the door, and when you first turn the key. It rattles, and a faint white screen comes up momentarily in the screen where the odometer/MPG/MPH info can be displayed. It wasn't doing that after I replaced the battery until that morning it almost didn't start. And it doesn't do that when I go to start when the engine is warm or the car has been driven in the last few hours. That rattle in the instruments seems to be a telltale that the battery is weak.
We have a 16 Dart my wife drives every day. Whenever I drive it(about once a week) I notice the same thing. It's always done it. I don't think that is a sign of a battery problem. I'd like to hear from a tech though that's familiar with these cars to see if they all do that. I haven't checked on a Dart specific website to see if they mention it at all. When the dash "rattles" the gauge needles swing wildly for a second before they settle down to their stops.
If you are having surgery soon I'd drive the car so the battery is good and charged. When you park it, disconnect the battery. When you come back to it, see if it still starts hard. If it starts normally, then there is a drain. If the battery is dead or the car starts really hard, then I think you can say the battery is junk. By disconnecting the battery after you've driven it for awhile, it should still have full charge after a week.
