I have been getting ready to take my truck out for the first run of the year this week and as I start going down the road leaving my house the truck starts running like chit. Form what my buddies could hear outside the truck, they say it is missing pretty bad and I can feel it inside the cab. The truck is vibrating bad, but the thing that gets me is the ses light hasn't come on yet. On my old off road w/ the 5.4 a coil pack shorted out twice, both times I am pretty sure I saw the light come on. I did wash my motor and it may have shorted out a coil. I am taking it to the dealer tomarrow, but I was looking for a little input. Thanks, Jason.

 

I agree, you probably shorted out a coil-pack. If it's vibrating as you said, you have a 'dead' cylinder/plug.

Dan