Q: What causes Cylinder misfire? Spark plugs, wires and coil pack already replaced 2005 Dodge Stratus

Hello - in addition to the components which deliver spark on command (which you have already replaced), are the components which determine when the spark should be delivered (crankshaft and camshaft position sensors). A bad fuel mixture will cause misfire as well. The components that ensure deliver of the correct fuel mixture (fuel system, injectors, air flow and mixture management components like the throttle body, air and coolant temperature components, engine management computer, etc.). Look for additional problem codes than the misfire indication - check fuel pressure. For assistance with diagnosis, I recommend a misfire inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.