Ok so here is my problem, my mustang has been stumbling off and on for awhile now and i cant figure it out Sometimes it will run great , then the next time i start it will run like crap.... I have changed plugs, wires, cap, button, coil, fuel filter. I have a fuel gauge and im running 35 at lidle and up to about 43 getting on it... I was told that if u unplug the iac while at ilde and it doesnt change that it's bad??? I know i just gave my life story just looking for some input thnx guys.