03' protege has headlights dimming and blower motor flucuates while cruising along not just at idle or pulling out.Battery replaced no change.new alt. belt also.Leaning towards alt.Never saw one act like this while cruising?

 

Alternator.
But before you shell out the money check all connections to the alternator including grounds. Inspect the cables too.
Have the alternator tested on the bench at O'Reilly's. OReilly's has better quality re-manufactured parts than Auto Zone.

 

Thanks for the reply.No O'reillys where I live.Did have Advance Auto check it after I did my own voltage tests.They said it appeared to be charging fine, but the "ripple" on it may be too high which could be a sign it is starting to go.When I did my own test under load the voltage did fluctuate a good bit, but held steady at idle.Compared to one of my other cars which help steady under load.

 

There ya go....