Diesel Bombers - Only runs good cold

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- 5.9 Liter CR Dodge Cummins 03-07 (https://www.dieselbombers.com/5-9-liter-cr-dodge-cummins-03-07/)

- - Only runs good cold (https://www.dieselbombers.com/5-9-liter-cr-dodge-cummins-03-07/133318-only-runs-good-cold.html)

Only runs good cold

I've got an 05 dodge 3500 with the Cummins 5.9. it runs great for the first 10-15 minutes of driving. It kicks into limp mode after running a while.

Two codes come on, p0206, and p2149. The codes refer to injector#6 and rear injection bank.

Injector #6 and the #5/6 injector wiring harness were both replaced to no avail.

Any suggestions to what could be the cause?

Heard possibly the ECM? Could it be the wiring between the ECM and the injector harness?