Trunk wasn't shut for 4 days and the car was completely dead. Jumped it very easily and ran errands for a couple hours without turning it off. Then I turned it off and went to start it 30 minutes later and it wouldn't start. Lights came on but didn't turn over. Jumped it again and drove it to O'Reilly's to test battery. They said couldn't get a reading on battery so it meant alternator was draining it because alternator was going out. Drove it home and turned it off and then restarted fine. Do you think alternator is going out?
My car has 50000 miles.
My car has an automatic transmission.
Hello, thanks for writing in.
If the vehicle started back up then it is not likely that the alternator is bad. If the alternator was bad, the battery would have been low and you would not have been able to restart the vehicle later on. It may be possible that after driving it around for an entire day, the battery is now charged enough to properly start the vehicle again. However, if the issues persist, I recommend having the battery and alternator tested by another place.
If you would like inspection help, consider having an expert automotive technician from YourMechanic come to your home or office to diagnose this issue for you and make any repairs as needed.