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failing alternator? what are the signs?

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so i'm driving home from work, and my "charge" light starts coming on at low idle, and above 2500 rpms... as the rpms increase past 2500, the charge light gets brighter and brighter.

 

is this a tell-tale sign of a dying alternator? or something else perhaps? battery is strong, only 2 1/2 yrs old.

 

140k miles, ea-82 spfi. whats the average death-mileage of a stock alternator? anyone have similar experiences?

 

thanks!

so i'm driving home from work, and my "charge" light starts coming on at low idle, and above 2500 rpms... as the rpms increase past 2500, the charge light gets brighter and brighter.

 

is this a tell-tale sign of a dying alternator? or something else perhaps? battery is strong, only 2 1/2 yrs old.

 

140k miles, ea-82 spfi. whats the average death-mileage of a stock alternator? anyone have similar experiences?

 

thanks!

 

I would say so

Most times, mine would cause the idiot lights to come on very dimly

Of course, it's much easier if you had a volt gauge on the dash

If you have a battery tester, monitor the fluid each day to see if you are losing batterty strength

Take your alternator to a parts store. They can usually test 'em. Checker has a machine right out in front that will test it for me.

don't forget to check the alternator and battery connections. bad connections at the battery won't allow the alternator to charge it properly. the end links should not be able to be turned by hand on the battery terminals. and the terminals and end links should be very clean, free of corrision and build up. same goes on the alternator end, the plastic plugs are the most notorious for failing with age, they turn to brittle plastic and short out.

 

what thye all said. many chain auto stores will test alt's for free, have them test it. the lights on the dash typically light up. address it now before fusible links or more start to fail. bad alternators do bad things to battery's as well. it is very common to replace both within a short period of time...replace battery then within 6 months the alt goes bad or replace alt and within 6 months the battery goes bad. keep an eye on the battery after installing the new alt.

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Thank you everyone. looks like I'll be heading to Autozone for a re-man'ed alt very shortly. time to do drive belts anyway.

 

Thanks again.

make sure you keep the paperwork, including the reciept, for the new alternator in a safe place - have gone thru a couple of replacement alt's in 5 years - but with a lifetime warranty, just take it, and the paperwork back to the store you bought it at, and viola - new alternator.

 

with a couple of old subies here, we actually have a "backup" one sitting on the shelf so there is no real down time waiting on one to get to the store (not many Subies around here, so they have to order one in)

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