I have a 2012 Dodge Durango 3.6 V6 with 206k miles. I bought it for dirt cheap because of this intermittent misfire issue on cylinder #5. The only fault code it's throwing is Ignition Coil Insufficient Ionization for cylinder 5. If I delete the code, the engine goes back to running absolutely normal as if nothing was wrong. After running the engine for a while, it will start to shake a bit and the same cylinder 5 ignition coil code will come back along with the misfire on that cylinder. I've replaced the spark plugs, ignition coils, and the connector to the coil, but the fault comes back. I did notice that whoever owned the car previously put a new PCM and did a questionable wiring job on the engine harness. I've been told all sorts of things by people on what could be wrong. I've been told its a bad camshaft, valve train issue, worn timing chain, to even a bad head gasket. However, the engine does not rattle, tick, knock, nor overheat in any way when running. It only shakes a bit from the misfire, but goes back to running smoothly when I erase the code with a scan tool.

Any guidance on where to look next is appreciated!