[srhaddon1]

The battery light on my car had came on and i had the alternator was making noises. I changed the alternator out with a rebuilt bosch. Put everything together and checked the voltage. Pre start it was about 11. After starting it dropped to like 10.8 and slowly died..... what should i do now? The battery light is no longer on and advanced auto keeps saying this battery is good.

 

[Solidjake]

Should be around 14 at idle. I would check your idler/tensioner pullies and belt to see if they are slipping or are worn out, if good then I would get another alternator and see if anything changes. If not then get a new battery. H8-AGM is what I have.

 

[Nohuri]

You could do a parasitic drain test.

 

[Official NOCO]

How old is the battery?