engine runs rough/missing on 2005 Ford F-150

when accelerating the engine misses really bad. If I back off the gas pedal it seems to smooth out some. It does not do this all the time but when it does it is when I am accelerating.

Asked by for the 2005 Ford F-150
I am a certified ford tech, and this is a common problem in the 5.4l 3v engine, this engine has overhead cam with variable cam timing (vct), it has phasers on each cam to adjust timing to provide more power or better mileage. but usually after 80k or so these phasers stick so at low throttle or high throttle the phasers stick and are basically backwards from what they should be. they are simple to replace but i would not recomend a DIY because there are special tools to hold timing chain and tensioners in place and if you loose where they are at, then you have to pull off the front cover and re-time the entire engine, most likely your warranty is out, so if you want it fixed then better start saving because it does not come cheap (about 15 bills)..........hope i was helpful
so this is a very common problem having same issues now trying everythimg please help
3 answers 3 comments
You should have a check engine light on and codes stored in the power train control module. Can you get these codes and post them?
engine icon light is on. have not had codes checked yet; will do that and get back to you.
That is a good place to start. Another thing I would do, and this goes for just about every vehicle made after 2000, have the software in the engine and transmission control modules checked to make sure it has the latest available. This can address weird problems that are nearly impossible to solve by regular diagnostic methods.
i was having this same issue with my 2006 F150 5.4l and i replace all the plugs and coils and it turned out to be a fuel filter. when you accelerate especially hard the cyclinders are starved of fuel. when you accelerate gently it will not do it all the time right? mine mainly did it between 45-50 mph and 70-85 mph. Fuel Filter is a lot cheaper option. Let me know if this fixes your problem