My check engine light went off a few weeks ago. I read the code P0301 for Cylinder 1 misfire. The jeep was noticeably running rough, lost power, and about 12 mpg. I immediately swapped all 6 plugs, wires, and the Ignition Coil. Cylinder 1's plug looked bad and appeared to have a slight crack. Check engine light went away, and 400 miles later came back. I decided to run a few bottles of Lucas Fuel injector cleaner through it and the light went off by itself once again. 800 miles later the check engine light returned... Does anyone have any ideas of what could be causing this to be so sporadic? My jeep has 121k miles on it, and I am getting 18 mpg, idles amazing, and has an increase of power. Am I looking at a fuel injector potentially or issues with Cam/Crank sensor? Any insight would be appreciated before I am forced to bite the bullet and take it into the shop.

Thank you.