Chrysler Repair: 2002 Chrysler Sebring: hard starting, chrysler sebring, voltage gauge

Question
QUESTION: My car has been acting weird for about two or three weeks. When you are at a stop light it starts to stutter, like it wants to shut off. A few days ago I tried to start it and it wouldn't. It would crank but not turn over. I got a jump from someone and it was fine. Even when I got to my destination and turned it off and turned it on, it started immediately with no hesitation. Its been driving fine ever since. Today I drove it and I got stuck at the store, with the same problem. It wouldn't start but got a jump and it started fine. But when I was at the stop light it felt like it didn't have a lot of power. Like it might shut off. What could be wrong with it? Do I need a new battery or is my problem bigger than that? Thank you so much

ANSWER: Hi Monica,
Try to get a fault code readout from the engine control module using your ignition key. Turn it: "on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see the mileage change to show some 4 digits numbers preceded by a P. Let me know what they are and we'll go from there. Also tell me the size (L) of the engine when you send me the follow-up answer.
It might be the battery since it starts with a jumper. How old is the battery compared to it warranty life?
Roland

---------- FOLLOW-UP ----------

QUESTION: I did the "on-off-on-off-on" and it showed nothing but the mileage. No code preceded by a P. The engine size is 3.0. Thank you so much for your help. I wish I knew more about cars.

Answer
Hi Monica,
How about the question of the age of the battery? There is usually a sticker on the battery that states when it was installed in the vehicle so look for that information. I assume that you don't show a low voltage reading on your battery voltage gauge on the instrument cluster as the other possibility is that the battery is not being charged suffieciently.
As to the fault codes, go to a nationwide autoparts store, such as Autozone, where they will use a plug-in code reader to get the fault codes, and do that for free. Get the specific numbers, ask what they mean, and then let me know what they are.
Roland