I have a 2003 dodge Intrepid SXT 3.5L miles on car now is 99207. The engine was replaced near 70000 miles. Cylinder #6 keeps missfireing tryed new spark plugs and new coil and it is still happening.Tried fuel injector cleaner to. The trainsmission is sticking in 2nd gear when car is comming to a stop and when rpm is comming down. When on the highway the car is running fine at high speed. When taking the exit and the RPM is comming down the car will stick in gear. I would have to shut car off and start back up and car is fine till next time.I have codes which are PO700, PO354, PO731, PO841, PO356, P1776. Hopefully you can give me some ideas.

Thank you

 

get a service manual and follow the diagnostic procedure as clearly directed. Or try doing a Google search for each code and see if there's any diagnostic tips or procedures to direct you in the repair of these problems. that's my idea.