what causes my 4.6 to stumble
i have a 97 mustang gt 4.6 with 157,000 miles on it and it's got a problem where the engine is stumbling if i give it too much throttle. i've looked in my chilton's manual and it says it's either the ignition or fuel system. i've just put new plugs, coil packs, fuel filter and fuel pump on it not too long ago. so what my problem?