Originally Posted by crump2004F150

No I haven't had the plugs changed yet. The truck has 163000 miles on it and it has no codes shown with a standard code checker. I had a friend listen to it when I gave it full throttle leaving his house and he cld hear it missing. It don't give that hard shake when it's under full throttle. Only at cruising speeds and going up a slight hill it's very noticeable.