Ok, this happened a month ago...I went on vacation for a week, came back, and my 97 Sentra(1.6L, auto) won't start. So I jump started it and everything's fine. I guess the battery didn't keep its charge for some reason. Went to autozone afterwards, and batt, alt, and starter all checked out fine. Fast forward to today. I started the car up, and it cuts off after 2 seconds. The car won't start afterwards, but it sounds like the battery has enough juice. The radio and lights work. I tried to jump start it, but it didn't help. I just got my alternator replaced about 6 weeks ago, and my starter works, so it sounds. There's just something keeping the car from starting all the way. I don't know what to do.