The diagnostic fault code just tells you the circuit or system that needs further diagnosis, or the unacceptable operating condition. In this case it's random misfires that affect all of the cylinders that must be diagnosed. The dealer could not tell you what to repair because the cause has not been diagnosed yet.
We never approve of throwing random parts at a problem because that is the most costly and least effective way to solve a problem, but in this case, based on the mileage you listed, worn spark plugs would probably be the best suspects. Other things to consider include fuel-related problems. Fuel pressure could be too low. If you are using a higher octane gas than what is specified, that will be harder to ignite and can lead to misfires. Old, stale gas may not burn well too.
You are looking for things all the cylinders have in common. If you had one bad injector, (very rare), or one weak ignition coil, you would have a fault code for a single-cylinder misfire. For example, code P0302 would indicate cylinder two is misfiring. Be aware too the engine computer can detect these misfires when they are still too subtle for you to feel them.
Take a look at this article for more information, but skip the section about mass air flow sensors. Chrysler never used that sensor on any of their domestic car and truck models.
https://www.2carpros.com/articles/engine-misfires-or-runs-rough
May 9, 2018 at 2:30 PM
