Alternator or timing belt- not sure

MNKREBS

MEMBER
2008 CHRYSLER SEBRING
102,000 MILES

My car had begun making a noise lately, similar to a manual transmission when you are gearing down from one gear to another. Whenever I slowed down, it would hum as it was slowing down. The engine also made a rattling noise, like something was loose and hitting something inside the motor. The battery light came on a few days ago and stayed on while I was driving. When I checked the owners manual, it said that if that happened it was the charging system. My car died on me the other day. All of the lights on the instrument panel came on and I pulled over. I had a two truck come to tow it, and the driver jumped it and said it wasn't the alternator, it sounded like the timing belt. It can be jump started with cables, but won't stay running even with the cables still attached. Any ideas on what it is and how much it could cost to fix?

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

It sounds like you have a bad alternator.
The first thing you need to check is the alternator as well as the battery. When a alternator does not operate as designed it can also make the battery go bad.
Test the alternator output. If you are unable to keep the vehicle running to test the output in the car, you will have to take out the alternator and do a bench test.

https://www.2carpros.com/articles/how-to-check-a-car-alternator

When the alternator is unable to keep the battery charged you will get the battery light on the dash. It can be either due to a bad alternator or a bad wiring from the battery to the alternator.

https://www.2carpros.com/articles/how-to-replace-an-alternator

It will also be a good to do a load test on the battery. As the battery could have gotten bad it it was severely discharged by the alternator.

https://www.2carpros.com/articles/car-battery-load-test

I have attached diagrams for your reference.

Please let me know of any questions.
Thank you.

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