'97 T&C 3.8L: One cylinder out, what happened?

[70challenger]

Driving down the highway when suddenly engine starts running rough, some vibration , loss of power (no unusual mechanical noises) and check engine light starts flashing. I travel slowly to dealership. They diagnose 1 cylinder out and apparently not electrical problem. They say maybe valve problem,etc.and will need to remove head. I was hoping for an easy fix on this but it might turn into a pricey venture. It doesn't sound like a valve to me. Are 3.8's prone to something like this? Any ideas on what might have happened here and best way to proceed?

[RickMN]

This engine is known for cracking the rocker arm towers on the corner cylinders. Usually happens on cylinders 1, 2, 5, or 6. Only way to fix is to replace the cylinder head. When they crack the engine makes a ticking noise.

However, this engine is also known for carbon buildup on the valves.