So my car had a hard time starting this morning. Shortly after starting it stalled and wouldn't turn over, the starter getting slower and slower like a drained battery. I jumped it and it started and ran fine. I left it for a few hours then just tried restarting it and it fired up as normal. Last night, driving home, I noticed that the headlights would intermitently dim then brighten.
Any ideas on this one? I'd like to not have to replace electrical components on a trial and error basis. How do I know if I need a new battery or alternator or determine possible other causes for this behavior?

Cheers,
Matt

 

Check to see if your battery is at 12V. Check for drains in the circuit. If the battery checks out, it's probably your alt.

 

with your headlights going from dim to bright, sounds more like the alternator is dying

 

Yup. I'm 99% sure its your alternator. My car did that a few months ago where I would jump start it and then 10 minutes later, the car would just die while I was driving.

 

yea, otherwise it would charge up. Also, with the wavering power, thats a sign that the charge is fluctuating. If it was constantly charging (and the alt was good) it would be fine. The bad alternator might MAKE your battery bad, so get that check, but you need a new alternator.

 

Thanks for the help!

 

Do I have options for a 'beefed up' alternator? Does that even make sense (would a higher-rated alt actually do anything)?
Thanks,
Matt

 

I got the thing diagnosed this morning...it was only the battery. Did you guys know that he Max has a VERY expensive alternator?

 

must of cost you $85 to just get a diagnostic from nissan? Yep maximas alternators are not cheap. There was a recall on many of them