I have a 2005 ford 6.0 with 115000k miles on it that hesitates when running( feels like it's missing)this occurs most between 1-2000 rpm's and doesn't have an issue when the give heavy amounts of fuel. It also is slow at starting on cooler mornings i don't know where to begin.

This link may help:

https://www.askmehelpdesk.com/cars-t...ml#post1415281

Be sure you have changed both fuel filters recently.

I have changed both fuel filters.

As everyone knows there is turbo lag, which get worse due to hauling a large or over sized load, Just check it.Take your throttle body off and check that turbo is spinning freely or not.. If it is going fine then it might be the bearings or shaft issue.. Some times oil leaks is also cause of this hesitation problem... Hope this helps you..
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