Truck vibrates at idle...?
 

My buddys 07 6.0 runs fine when your driving but when stopped at a red-light or something the engine vibrates and makes the while truck shake like its missing or something. It has a high pressure fuel pump on it when he bought it. Any ideas?

A high pressure fuel pump? What is that exactly? Truck only needs 55psi to operate correctly.

I know mine idles a lot smoother with fresh fuel filters. I never notice it, until I change the filters.

man i dont really know. Theres like a small psi gauge on top of his engine in the middle of the truck. a guy from ford told us it was a high pressure fuel pump and the guage read like 65psi.

He might have some sort of an aftermarket pump. Usually the gauge on top of the motor is from a regulated return setup, or it could just be a mechanical gauge put in there since you're not supposed to have a mech gauge in the truck (65psi of fuel inside the cab is a bad idea haha). Take a picture and lets check it out. When's the last time the oil/oil filter was changed, when's the last time the fuel filters were changed? Get under the truck on the drivers side right by the front driveshaft the factory pump is usually there. You can either have an adjustable regulator type pump like the airdog 2, which would eliminate that stock setup, or you could have an airdog 1 or a non adjsutable FASS pump which would just feed the stock setup. Let's try and get a little more info and we can probably help you out.:pca1:

Ok I'll get a pic of it.

Check engine light came one. Shooting trouble code P0278 cylinder number 6 contribution/balance. Whatcha got mdub?