Have a 1999 Grand Cherokee six cylinder which in the past two weeks has several times been difficult to start and then misses and carries on. Check engine light comes on. Shows a P302 misfire code for cylinder two. The problems is intermittent with the vehicle starting and running fine for several days at a time. What should I look for in order of the most likely problem.

Bad injector, spark plug, coil pack. Injector would be my first suspect, when they leak they don't set codes.