Hi, I have a 2006 GT 4.6 5speed 355 gear. My engine has a full Mac exhaust, GT500 throttle body, cold air intake, power pullys, Detroit rocker cams, I bought the car like this and it runs and sounds great! I have never until recently ran it from a dead stop, when I nail it from a dead stop it has a bad cut out then right back on, hall *** after that with no misses in any other gear? The fuel pumps have been replace, I have part numbers I will post later, though it might be a fuel problem? I called the mustang shop that in stalled the cams and they think its because I need at least 373 to 411 gears. I just don't think that's it, when it hesitates the engine light flashes on and off? Im an old school hot rodder and if I could I would switch it over to a distributor and carb!! I love the unreal power this little 4.6 puts out but need help with the bad stumble, I do have a controller of some kind that came with the car, I will post its name brand and model later when I get home. Thanks for any help!!!!