2016 Ram 1500 V6 cylider 6 misfire issue

[RonVV]

Replaced coils and plugs 15k ago. P00306 code came back on. Took it back for the issue. They tore it apart and found nothing. They moved coil and plug to a different location. Reassembled everything and same code came on later that day. Reset the light and it stayed off for a while. Came back on then went off the next day. Truck had a slight rough idle from time to time. Now it's more frequent.
Any advice?

 

[SitKneelBend]

Replaced coils and plugs 15k ago. P0036 code came back on. Took it back for the issue. They tore it apart and found nothing. They moved coil and plug to a different location. Reassembled everything and same code came on later that day. Reset the light and it stayed off for a while. Came back on then went off the next day. Truck had a slight rough idle from time to time. Now it's more frequent.
Any advice?

I'd have the fuel injector on cylinder 6 tested. If it's bad, I'd consider replacing all injectors on that bank while you're in there. I had cylinder 2 injector go, followed a few months later by 4. The dealer wanted to replace 6 too but the warranty wouldn't cover it (I would have paid if they asked me but anyways). If you plan on doing the tests yourself with a multimeter let me know and I'll post the dealer notes of how they diagnosed it.

 

[crash68]

P0036 code came back on.

This is error code for an O2 heater issue.
Is the code your getting a P0306? That's the error code for #6 cylinder misfire.

Aside from from just throwing in a new set of injectors, the next steps would be check if the valves are moving, and a compression test.