I brought my liberty back from the dead. Developed a misfire on cylinder 3. Brought it to a shop and they charged me 50 dollars to tell me the coil was good and that it was either carbon buildup, clogged/ bad fuel injector, bad spark plug, or dead hole in the cylinder. After throwing the parts canon at it and nothing working, I was about to give up and buy a new car. Less than an hour before I was about to meet up with someone to test drive another car, I decided to check the ignition coil anyway. Swapped the cylinder 3 and 5 coils and suddenly my p0303 code changed to a p0305 code. A 35 dollar coil later and it runs like a dream again