car thread yo: what be the problem with my Alt/Battery

[LS20]

Its a 1993 Nissan Sentra

ok here's the deal, at about the new year i was driving, and then the Parking Brake + Battery light came on... i drove it home, the next day the car wouldn't start

I took the car to Autozone to have the OEM battery tested, and they said it was weak, so I bought a Duralast. Also, my dad and my uncle found that my alternator was defective (For my 2 years of ownership I've never had it replaced) so they replaced it with a remanuf. unit from O'reillys.

That unit worked for about 2 months, then one day the car got weak, showed the 2 PB+Battery lights, and died. A guy I know checked the alternator with an voltage meter and it showed 12V--apparently theyre supposed to put out 13.6V. So I chunked that alternator, bought another one from O'reillys, and installed it myself. That one also lasted another 2 months till now... 2 lights came on again

Now the alternator is showing 12V straight... if i connect the 2 battery terminals with the volt meter, it'll show ~11.5V.

My question is what could be causing all these problems... im naive to think it could be the battery since its a new battery. also, i lost the receipt so i cant get an exchange on the battery . i can, however, get the alternator exchanged. isnt 12V good enough tho? or maybe BOTH are bad and need replacing? some people suspect that there is something in my electrical system that could be killing the alternator, but I also hear that remanufactured alternators--especially cheap ones from AUtozone/Oreilly--tend to die quickly and people have had strings of them failing...

FYI the battery connectors are clean--no corrosion. The only extranneous thing hooked up on the car is 1 audio amplifier, but its rarely used and doesnt draw alot of power.

 

[amdforever2]

uhhh arent they supposed to have a one year warranty?

i replaced my alternator today

$63 with one year warranty

 

[XZeroII]

Because of your crappy subject title, I didn't even read your message text.


Get a new battery, and a new alternator. Or just get a new car.

 

[Cuda1447]

Ya the title made me want to kick you...


*kicks*

 

[LS20]

Originally posted by: amdforever2
uhhh arent they supposed to have a one year warranty?

i replaced my alternator today

$63 with one year warranty

yeah, it actually has a 2 year warranty--hence i am able to get an exchange on the alternator. however, i dont think i can get a return to buy a completely new alternator ... or atleast one of better quality from napa

more importantly, i want to know whether its only my alternator that is bad or if the battery is also defective and, consequently, drawing too much power and putting strain on the alt

 

[Kaieye]

I had the same symptoms as you did - almost. I changed the battery AND alternator and found out later that a wire that came straight from the alternator to the battery looked physically connected- but electrically was not flowing. After my friend and I removed the suspecting wire and resolder it, it worked!

Good luck.

 

[MercenaryForHire]

Originally posted by: Cuda1447
Ya the title made me want to kick you...


*kicks*

/kicks LS20 again for good measure

The proper title would be

YACT: 93 Nissan Sentra - Alternator or Battery issue?

Maximum exposure, minimum eThuggage. Yo. Dawg.

- M4H

 

[imported_Papi]

I'm no mechanic but I think if your alternator is not working properly it will drain your battery. Hence you will need new of both.

Thats what happend to my hubby with his Z24

 

[Gage8]

sounds like you need to find someone who is more experienced with alternator's 'n such. Maybe take it into a trusted mechanic to get an evaluation and then do the work yourself.

 

[Quixfire]

First, proper voltage at the battery with the vehicle running, you called it "alternator is showing", is a range of 13.8 to 14.4 Volts.

Second, alternators with Internal Regulators can burn them self out by consistently charging a week or low charge battery. If you amps are creating a draw on the system you battery will discharge and then the alternator has to recharge it.

Third, you may have a bad ground at the alternator, which will cause an alternator to fail repeatedly. Take a test light; connect one end to the negative side of the battery, black or ground (-), and the touch the alternator housing. The test light should shine brightly, if not then check you engine ground straps for corrosion or a loose/broken connection.

 

[grillmasterP]

Originally posted by: LS20
isnt 12V good enough tho?

alternator should be producing about 14V - Needs to have >12V in order to charge the battery properly otherwise you will be using the charge that the alternator is producing as you are driving. Alternator should be producing more than you are consuming.

My next suggestion would be to either stay away from that particular brand of O'reilly remanuf. , try a different parts place of buy one with a lifetime warranty so you can exchange it it it dies the next time.

Are you driving or creating any conditions that would cause the alternator to die prematurely? Driving through high water, mud, or obsessively hosing down your engine bay with a pressure washer?