I have a 2006 dodge stratus it's ran great and one morning I went to warm it up and it started but when I went to leave it cut off and wouldn't start back so I got a new battery it ran great for a
take the alternator off and see if it is bad cause the battery would drain in a week or so
Check the battery cables first and then check the voltage at the battery with the engine running. If the alternator is good voltage at the battery should be 13.8 to 14.6 plus or minus a few tenths. If when running the voltage is in the 11 to 12 volt range the alternator is suspect.