probably brushes in the alternator are about gone, but you COULD open the hood and check for a loose belt first..................
While I'm idling my 85 S10 Blazer charging indicator hovers around 12.5
> volts ( it use to stay around 14.5 at idle ) but when I accelerate the
> battery light now flashes on and off , so I'm wondering if this is an
> indication of a bad alternator, battery, or a loose belt..... In the past my
> charge indicator light always remained around 15 volts at high speed.... now
> it just sits at around 13....
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