if you beat on your car alot you may want to check the connections on your battery. check the ground to the engine, connect. that may be it. i had a horn wire wiggle loose once.
I have seen some posts that have described worn alternator brushes "bouncing". Search for alternator brushes for more info.
I have had a similar problem with my SE for the last month or so & it is happening at lower & lower RPM, so I ordered some new brushes from NAPA. I'll install them next weekend & let you know if it cures my problem.
I had the same problem...I negative battery cable was corroded and would slip on and off, and my car would cut off, but sometimes the battery light would just illuminate. Check your battery cables...
i had a horn wire wiggle loose once.