I have a F150 Lariot With the 5.4 Triton. It only has 80,000 miles on it and has a strange misfire sometimes. Sometimes when going down the HWY and you go to pass or floor the accelerator, it will go to missing and popping, and sometimes it will take right off like it is suppose to. I have no idea what might be causing this. It runs excelent most of the time until you floor it. the check engine light started flashing the last time it done this and now is staying lit up. Any help on this problem would be great. Thanks.
What about the coils too or just the plugs? What plug should i go back with. I have heard bad things about the two piece factory plugs and have also heard bad thing about the champion one piece replacement plugs. Has motorcraft corrected the issues with thier plugs?