I searched this forum and found several P0304 code problems but all dealing with the Pentastar 3.6L engne. My JK is a 2011 with the 3.8L. My engine light is not blinking just steady on. There is no noticeable performance issues. I cleared the code but after a couple of trips it came back on. Today I changed the spark plugs hoping this might be the cause. Somewhere I red that the fault code/engine light will clear itself after a predetermined number of drive cycles after problem is fixed. Can anyone confirm this information?