Here you go...
Battery Light Flickers During Acceleration!! Either you have a weak or bad cell in your battery or your alternator is on it's way out. Mine started doing the samething the day after I accidently left my parking lights on something like 5 times in the same day!!
Bear in mind that I have a Duralast battery that is only about 4 or 5 months old. Also, a fellow CEGer that lives a few hours from me.... His does the samething, on his we have been able to determine that it was his alternator. At 6000 RPMs, his voltage output just falls on its face.
