fast efi problem

its a msd e curve. i have the fast ez efi, not the 2.0 so the only thing the dizzy does is supply tac siganal wich i understand is crutial. i originally had my tac and the fast plugged in to the dizzy and on friday the tech guy said that would be the problem for sure. i unplugged the tac, rerouted the wires and stll no change. i'm sure it's a malfunction of the fast system, this thing ran great all last summer and the first couple hundred miles this year and then started acting up.