[RABarrett]

Considering the circumstances, you may be experiencing either a coil or plug wire issue. As the engine warms up, the mixture leans out, causing the demanded voltage from the ignition to rise quickly. This rise in voltage can cause a defective coil or wire to start arcing to ground. This will cause the misfire, the code set, and the conditions occurring during warm driving. Just a heads up, burned valves will cause a misfire during cold as well as warm conditions. As a word to the wise, it is more telling to compare the pulse duration on the injectors. Suspect a broblem only if the duration is considerable different from other injectors. I suspect a coil, or plug wire. Ray