fuel regulator? Are you running hoses and not tubing? could be colapsing the hose, no fuel then. But if you had E-85 in it. Rebuild the carb and clean it out. Mine would not idle, revved fine, idle = crap. rebuilt carb = charm.
E-85 is kind of nasty stuff. you will see a gray/black/silver sediment in the bowls of the carb.
