I have a 1998 Mustang GT. My problem is this...when I accelerate at a normal speed the voltage drops momentarily then goes back to normal(or close to it). But when I "take off" and unleash it. The voltage really drops and my battery light comes on. Again going back to normal once I get up to speed.

I recently replaced: The battery, The Belt, and the tensioner...? and had the alternator checked. Any suggestions would help.

 

did you reroute the belt correctly and make sure the battery terminals are connected tightly?

 

Yes. But this problem was happening prior to replacing everything....and continued even after. Took it to my local parts store and found out thats its my Alternator. Checked it under load with the engine revved up(thats when the problem occured) and it showed really low voltage. New Alt. is in order. Thanks for the reply!