A little while ago I had my check engine light come on. I pulled the code and it said that cylinder 4 had a misfire. I figured the plugs, boots, or coils were going bad since I had a little over 80,000 miles. I replaced them for all four cylinders and the code went away for about two weeks. Then the light came back on with the same code. I swapped the plug, boot, and coil from cylinder three to cylinder 4 to rule out those parts being the problem. Again the check engine light turned off for another week and a half or so then right back on with the same issue. This time it only took a few days for the light to turn off again. But faithfully after another two weeks or so, it came back on. At that point, I took it to a mechanic to have them do a pressure test and the results were: 1)140 2)150 3)125 4)133. This gave me more questions than answers. Which brings me to now. Has anyone had a fusion do this? Or does anyone have any suggestions on what to check or do next?

 

Have you tried cleaning the ignition coil electrical connector and checked the wiring?