I have an 05 Dodge Grand caravan that I got used from my grandma. I play in a band and in the past couple years I’ve taken the van on 2+ cross country 5000+ mile tours. It’s been pretty reliable.
Recently, someone broke in and tried to hotwire the van. I found it with the steering column cowling ripped off and the lock cylinder battered with a brick, but they were unsuccessful thanks to the anti theft system. Also, when I found it, the battery was dead. After some research, I convinced myself I needed to replace the immobilizer anti theft unit, because the would-be thieves had smashed the ring antenna of my old immobilizer. I managed to splice the circuit board from the old immobilizer into a new one I bought, and I used my roommates Prius to charge my battery and start the car.
This was about two days ago - I successfully drove the van to work on that day (a ~45 minute drive). However, when I got off work about 4 hours later, the battery was dead again. I work on a college campus and a campus cop was nice enough to help me jump the battery so I could get home.
However, on the way home, I pulled over to make a phone call and put the car in park for a minute. After some time, the lights on the dash started to flicker and I started to feel the engine sputter and something made a kind of grating noise. I gave it some gas and started driving again, and the problem went away.
Fast forward to today, I try to start the van to go to work and the battery is dead again.
My question is - do you think this is a battery problem, on account of the car is ageing (170,000 miles), or an alternator problem? Or, is it a combination of these? Or it it neither, and I just need to drive it for a long time to charge the battery back up to full?