Possible alternator/battery problem
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Melting Slicks
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Possible alternator/battery problem
I typicaly have 13.5-14 volts showing on my battery display on my 86, but lately I have noticed that when I am at a stoplight the voltage drops and the red rectangle on the LCD lights up, and the voltage is dipping below 12 volts. , also when starting car the red light flashes showing around 9 or 10 volts. I had autozone check battery and alt, said they are ok....but I still am worried that their may be a problem. could it be the alternator brushes or bearings? it only happens when stopped, so since the engine is not at high RPMs, doesent that drop the output of the alternator?
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Re: Possible alternator/battery problem (ir0nmaiden420)
From what you say, your voltage sounds normal. It can drop alot at idle depending on what accessories you have running. But that red light should not come on at idle.
Dont ever trust the in-car gauge, mine is off by .6V, you need a real voltmeter and check the reading on the battery.
My problem, and I had to replace both the alternator and battery last summer, was poor starting when hot. The alternator was dying and pulling battery power to run the car, and that hurt the battery and eventually I had a dead cell.
Dont trust Autozone either, they dont ever get it right, they said my alternator was perfectly fine before I eventually replaced it.
[Modified by vader86, 9:48 PM 4/20/2004]
Dont ever trust the in-car gauge, mine is off by .6V, you need a real voltmeter and check the reading on the battery.
My problem, and I had to replace both the alternator and battery last summer, was poor starting when hot. The alternator was dying and pulling battery power to run the car, and that hurt the battery and eventually I had a dead cell.
Dont trust Autozone either, they dont ever get it right, they said my alternator was perfectly fine before I eventually replaced it.
[Modified by vader86, 9:48 PM 4/20/2004]
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Re: Possible alternator/battery problem (ir0nmaiden420)
You probably have a dieing alternator. The red battery symbol light on the dash tells you that the alternator is not charging the battery. When the battery is supplying all of the electrical power, you should expect the voltage to drop below 13 volts. Unless you have almost every electrical device on in the car, the idling voltage should stay at 14v (engine cold) to 13v (engine hot).
