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Alternator or battery?

Old 07-19-2006, 07:35 PM
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Twisted
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Default Alternator or battery?

So, recently I've noticed that my volt guage has been reading lower than usual. I put a meter on the battery today, and the voltage fluctuated between 12.55 and 12.60 volts. It should go up past 14 volts when revving, correct? Oddly, the higher I revved the motor, the lower the voltage went. Do you think it's my battery or my alternator that is bad?

It seems like the alternator to me. What is a normal price to pay for an oem alternator?
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Old 07-19-2006, 07:36 PM
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I3atR!ce
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Default RE: Alternator or battery?

if you want... you can take your alt to a place like autozone and have them test it for you, then you can rule that out.
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Old 07-19-2006, 07:38 PM
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Twisted
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Default RE: Alternator or battery?


ORIGINAL: I3atR!ce

if you want... you can take your alt to a place like autozone and have them test it for you, then you can rule that out.
I think I'll do that. Just trying to get an idea of what to expect. Thanks for the reply.
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Old 07-19-2006, 07:38 PM
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randy78045
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Default RE: Alternator or battery?


ORIGINAL: I3atR!ce

if you want... you can take your alt to a place like autozone and have them test it for you, then you can rule that out.
i believe the can test the battery with a load as well... an i dont think ya have to take the alt or battery out for their diagnostics...
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Old 07-19-2006, 07:39 PM
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sc94gt
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Default RE: Alternator or battery?

Could be the voltage regulator on the backside of the alt.
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Old 07-19-2006, 07:48 PM
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lookinforastang
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Default RE: Alternator or battery?

pretty sure u can get a OEM alt cheap with a core charge

or u can just upgrade to a 160 alt should be around $150
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Old 07-19-2006, 07:55 PM
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gspfunk
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Default RE: Alternator or battery?

Start the car and disconnect the battery while it's runnig. If it dies or tries to, your alt is bad.
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Old 07-19-2006, 08:01 PM
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89GTRed
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Default RE: Alternator or battery?

pretty sure u can get a OEM alt cheap with a core charge

or u can just upgrade to a 160 alt should be around $150
+1 they look MUCH better than stock and you will be well off if you ever get underdrive pulleys or a good sound system or whatever electric stresses you may put on it.
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Old 07-19-2006, 08:36 PM
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WHITESTALLION84
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Default RE: Alternator or battery?

DO U HAVE A SYSTEM ON YOUR CAR....CAUSE THATS THE SAME THING THAT STARTED HAPPENING TO ME WHEN I GOT MY SYSTEM...I FIRST REPLACED THE BATTERY CAUSE THEY TOLD ME THE ALTERNATOR WAS GOOD...THAN THE ALTERNATOR WENT OUT THAN I REPLACED THAT...BUT I STILL HAVE A PROBLEM WITH MY VOLTAGE SO I JUST TURN UP MY SYSTEM TOO MUCH...I GOT THE OEM ALTERNATOR WHICH I REGRET.
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Old 07-19-2006, 08:40 PM
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Twisted
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Default RE: Alternator or battery?

Thanks for the replies everyone. I'm getting ready to go to my mechanic to have the system tested. I don't have a high powered stereo system, or anything else that would put excess strain on the system. I guess the alt is just tired...at 110k miles. I just hope I can afford to get it fixed after having spent all my money on my new clutch.
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