My truck is an 07, 5.4l seems to have a random shudder. All spark plugs were changed less than 2 months go, I just changed all cop's last week after reading it was a possible cause. Also replaced the fpdm. I can feel it in the gas pedal and floorboards and also the tone of the truck changes, usually only last a couple seconds then back to normal. The truck also has edge cs tuner, s&b cai and mbrp exhaust. Any help or ideas would be great