[baxternick]

I have had a check engine light on and off for the past year. Always was a bank 2 code for to rich, or to lean. The engine would hickup somtimes at stop lights, and when under a good load like pulling trailer. Now the truck misfires all the time during acceleration. Usually between 1500-2000 rpms. The truck has a new coil, plugs, and plug wires in the last year, and also new cats. It is a 97 f150 with the 4.2l. I also notice some spark knock every once in a while when under heavy load. With the plug change I used platinum plugs. Everyone said they are crap and pull them so I did and got the basic autolite plugs that were like $3.00 each. The problem did not change a bit with that change. The only thing I can think of is maybe an O2 sensor is shot. Any help would be awesome! Thanks in advance!