Bad alternator???
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Safety Car
Joined: Jun 2002
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From: Arnold Ziffelville CA
Bad alternator???
How can I tell if my alternator's not charging? Y volt guage says I'm running 12.1 volts and when the headlights come on it starts dropping. Shouldn't the volt guage go up when I give the car gas? Thanks
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From: SE NY
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Re: Bad alternator??? (reyderz86)
You should read 13.x Vdc with a high idle and accessories on.
When my alt died it had no output and voltage was below 12 Vdc.
You can pull your alt and have it checked to be sure.
When my alt died it had no output and voltage was below 12 Vdc.
You can pull your alt and have it checked to be sure.
Drifting
Joined: Aug 2002
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From: Yakima WA
Re: Bad alternator??? (reyderz86)
I just replaced mine. Bought a new battery first, but voltage low indicator came on shortly after install. Replaced my alt and problem was solved. volts read 13.8 or so now. They are very easy to replace, believe me. I am not that mechanically inclined and I did it myself in probably 30 mins.
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From: Almost all Skyline Cruises Vettes at Waterside 1-5
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Re: Bad alternator??? (reyderz86)
In a perfect world, the volts should remain constant regardless of RPM, once you have gotten over the initial start up phase (10 to 30 seconds depending on how long the car has been sitting and how hard you had to crank it)
!2.1 volts is an alternator that is about to leave you stranded! I had one that crapped out in the middle of a busy intersection
Suggest you change it
Jack
!2.1 volts is an alternator that is about to leave you stranded! I had one that crapped out in the middle of a busy intersection
Suggest you change it
Jack
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Joined: Mar 2001
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From: Cincinnati, Oh USA
Re: Bad alternator??? (reyderz86)
The red battery symbol light should be on in your dash showing that the alternator is not charging the battery. 12.1 volts is indication of a discharged battery. Fully charged is 13.2 volts. Cold, you should see 14.3 volts on your dash voltmeter, engine running, low electrical load. Hot it will be 13.3. Idling with heavy electrical load , the voltage will be the battery voltage and should pick up to 13.3 when you get underway. 12 volts when you are underway and you have an alternator that is not working.
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Joined: Jul 2001
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From: Glendale, AZ
Re: Bad alternator??? (jfb)
The red battery symbol light should be on in your dash showing that the alternator is not charging the battery. 12.1 volts is indication of a discharged battery. Fully charged is 13.2 volts. Cold, you should see 14.3 volts on your dash voltmeter, engine running, low electrical load. Hot it will be 13.3. Idling with heavy electrical load , the voltage will be the battery voltage and should pick up to 13.3 when you get underway. 12 volts when you are underway and you have an alternator that is not working.
i had my alternator go bad a few weeks ago.....funny thing was, it was running at 11.9 volts at high RPMs and at idle it went up to 12.1 :crazy:
