2003 Harley Davidson F150 5.4 SC.
Engine has a miss/stumble in it when the throttle is barely open. Most evident at 45 mph. What is weird is that it wont do it all the time. There are is no service light on, and no stored codes in the computer..... 23,000 miles.
Any help would be greatly appreciated !!
Thanks

 

I had the same problem on my 4.6 you probably have a cylinder missfiring.. if your check engine light is on check the code and see which one. My #6 was missfiring ended up being a very slow leak from a radiator hose that went above it.. tightened the clamp end of problem.