Pretty much anything besides rust coloured.Belts may not be slack with underdrive pulley. It is a smaller crank pulley for faster engine spool-up. It won't spin the belts/alternator fast enough at idle and slower speed, possibly resulting in dim lights and such. This is a total guess, but I am guessing most aftermarket pulleys would be colored. Blue, gold, red.?.?
What does FML mean?I been told new bat might work. But ima pull my head unit out for now. See if that's the prob.
Fml