i have a 98 v6 mustang with and i just put an underdrive pulley on and now when ever i come to a stop when i have the heat and lights on the,thebatterygauge drops below the battery emblem and the light dims what can i do to prevent this or fix it and keep the pulley


also sometimes it wont start right away it take a few cranks would that also be because of the underdrive pulley

 

Your alternator isn't charging properly due to the underdrive pulley. If it continues to be a problem swap out the origanal pulley.