2003 Ford Truck 03 f150 fuel injetor dumping fuel in cyl 3

i have a 03 f-150 with 4.2l v6 i put new coil pack plugs,wires....the injector was not working in cyl #3 i replaced it now its smoking like a train and fouling the plug out in that cylinder it stops when i take the plug off its definetly dumping fuel in that cyl what could cause this beside a faulty injector which is new but i will be switching in the morn with different cyl to see if it does the same thing. ????????????????????????????????????????????