My 2000 cherokee is idling rough for about a minute after I start it and then it clears up. Check engine light is on and showing code P0306-misfire on cylinder 6. My spark plugs, boots, and engine are less than a year old. The rest of the jeep has 208,000 miles. Would appreciate any ideas on things to check. thanks

 

Injectors would cause a misfire too - easy to check - just swap no6 for another one, and see if the misfire moves..