Let's talk Alternator
Drifting
Joined: Apr 2008
Posts: 1,316
Likes: 2
From: St. Louis Mo
It sounds like it is a bad alternator. The Voltage Regulator may be bad in it(internal vr), holding the volts down to 12 instead of 14-14.5. Like stated above, take it off and have it checked out at your friendly neigborhood auto parts store! 
Tech Contributor
Joined: Dec 2003
Posts: 19,384
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From: Horncastle Lincolnshire, England
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What you should see on the DIC is 14V or so at higher RPM immediately after start dropping off to 13V+ after a short while as the battery tops off. At idle its not uncommon for the voltage to drop slightly as the alternator is not working at capacity. With the engine on, the DIC should show between 13V and 14.5V. 12V is quite low.
The DIC wont measure volts when the cars inginition is off. The only true reading for the battery at that point is across the terminals with a multi meter. A fully charged battery shows about 12.66 V and a fully discharged battery about 11.86 V.
As the guys say, its worth getting it checked.
Last edited by DeeGee; Mar 25, 2009 at 02:16 AM.
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From: The Sunshine State
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How difficult is it to remove the alternator?
Take it to Auto Zone,they will put a load on it to see if it's charging.
