2010 Charger, 3.5L with 38K. Running rough at idle only—the car is "bumpy" at stops, especially when slowly releasing the break—acceleration and running speed performance is normal—and there are is no stalling or backfires. Trouble code 0302 showed up after a few weeks of driving as conditions went from mild to definitely noticeable, but again, only at idle.I switched plugs and coils from #2 to #4 cylinder (facing engine, 1,3 6 on passenger side, 2,4,6 on driver.). No change...0302. Replaced the fuel injector with part from Dodge dealer on # 2 cylinder--same result, 0302.Replaced the ASD relay as I began reaching for straws…I have been reading a lot and have seen other suggestions--EGR valve, Vac. leak, Mass Air Flow Sensor which leads me to the main question: Do cylinder misfire codes point DEFINATEVELY to a specific cylinder? Or could a fouled plug/coil/ injector/on another cylinder be the cause of my 0302? If a vac leak is causing the 0302 that would not be specific to one cylinder, however vac leaks are top five in the troubleshooting sequences I have read about. Also, I now read and clear my codes at home—key bump x3 to read and F2 removed for thirty seconds to clear.)Thanks to all for any input. JV

 

You trouble shoot sequence should be Swap the coil, no fix? pull the plug and run a compression test.
If compression test pass, swap the plug and injector while you have it all apart.