I had a tune up about 1500 miles ago after Service Engine light came on. The truck ran good for the next 1200 miles. Now between 45mph and up whenever I get back on the gas the engine will skip or miss a little. Any ideas? Im sure I am overdue on changing the fuel filter and plan to do so next week.

 

Assuming you don't have a ck engine light on. Changing the fuel filter never hurts, but it's probably carbon buildup. Clean out the EGR and ports, the Idle Air Control valve and the DPFE hoses.

If the Ck Eng. light is on, have the codes pulled and repost.

 

If you are having a true "missfire" the check engine light (CEL) will flash during the missfiring. If this is the case your problem is mostlikely a coil and or plug problem. If the light isn't flashing than it is most likely fuel related.

As mentioned earlier it could be (if fuel related) carbon build up, clogged fuel filter, dirty injectors, all of the above.

 

Then it sounds like the problem is fuel related. No service engine light has flashed. I think I will start with changing the fuel filter and go from there.

 

I had a similar problem with my 99 4.6 after a tune up. Changed the fuel filter still missed. Ended up going back to factory ford plug wires fixed the miss for about 1 week ended up being a spark plug that had actually been arching right through the ceramic it had a perfectly straight burnt line right down the side my check engine light never came on. It can be frustrating finding the problem as alot of things can cause it but you might want to check those new plugs before you spend alot of time and money.