i recently got my codes read at autozone and it said i had a misfire on #4 cylinder i recently changed my coil packs my plugs and my wires changed and fuel filter still fill it but not as bad it has good compression but dont know why its still doing it only thing that i havent changed was the injector if anyone out there know about the problem or has been there and figured it out plz fill me in on my next step it has the 2 coil pack set up also could it be due to a bad 02 sensor because i notice that one of the three wires is pulled out so got to replace that thanks for your help

 

An Ox sensor never causes one cylinder or any cylinder to missfire.
With one wire pulled out of a Sensor plug you should have a seperate code for that fault.
Take a new look at the wire and plug boot for the cylinder missfire to see if the boot has an issue or not setting down on the plug.
Injector could be plugged.
Good luck.