Im new to this so Im not sure if im in the right spot. I have a 2005 F150 with the 5.4 engine. I am almost @ 90,000 miles and I feel like i have a miss in the motor. During a gradual acceleration it will hesitate and have a "jerky" feeling ONLY between 40-50 mph(and it doesnt do it all the time).. There is no check engine light or anything.. Could it be a coil pack going bad?? I know its time for a tune up regardless. Any info would be much appreciated

 

Is it when you're barely on the gas tryin to maintain a speed ?

 

Classic symptoms of a low grade misfire due to the plugs. At 90,000 miles, you are certainly due for a plug change. I'd start with that first. Make sure you stick with Motorcraft SP515s as there have been mixed results with Autolites and Champions.

In case you're not aware, changing the plugs in the 04-07 5.4 3V engine is quite an adventure. Do a search on on it first so you're fully informed....

 

Could be coil but your plugs are surely overdua and can cause similar symptoms. You will eventually receive a misfire code bit it may be a while.

 

Tprimo- yes, it only happens @40-50 mph maintaining a speed or slightly accelerating.. thanks guys for the help

 

Wow im new to this forum and its already helping my truck is doing exactly the same thing i think im gonna go buy some new plugs today!

 

My truck did the same thing. Changed the plugs and it runs like new. changing the plugs is not as easy as it sounds, do a seach.

 

There is a special tool made to pull out plugs if and most likely when they break. Napa sells one and I believe is around $70. Get it before starting. Also be prepared to disconnect and dismount your computer for the plugs in rear passenger side of the motor.