I have a 97 f150 4.6L w vin and have a cyl #3 misfire and air fuel metering not within manufacturer's spec codes as well as a few O2 codes which i'm assuming are from the misfire. i tried switching plug wires and still got same cyl misfire so it's not the wire. i put a new plug in and replaced the coil pack and that didn't do it either. so my consensus is plug, wire, and coil pack are not the problem. it has a little chug to it under light load but smooths out if i'm into the gas good. i dont think it's a cam or crank position sensor because it should pull a code but i'm not sure. any other suggestions as to what it could be are greatly appreciated. please help.

 

Compresion check.
Injecter swap.
Either one is a start.
Good luck!