Lately I have been noticing a lack of power while at WOT. When i come to a stop after going WOT the truck begins loping really bad and runs rough. My fuel pressure is staying right around 12psi and is not fluctuating. I have a new fuel filter (~1000 miles on it) installed. It only does it now and then and only does it after going WOT. Otherwise the truck runs smooth and has full power.

any ideas?

 

Injection pump could have internal probs, like an out of place oring or something. Almost sounds like its slightly sucking air. Just my 00.02, idk alot about the ve internals

 

my first thought was something was wrong with the VE. I had issues with it sucking air before and i would notice a fluctuation in fuel pressure and that is not the case now.

 

After WOT?
Is your fuel pressure lower than before at WOT?
Lift pump, fuel filter, dirty injectors?

 

no about the same. At WOT it has always dropped down to around 9psi and that is what it is still doing.

 

Take about a 4 ounce fuel sample from the fuel filter and let it set for a while in a clear glass container. Check it for water. Water can get into a fuel filter and cause a partial blockage by displacing some of the fuel.

 

ok, i will do that. It has been occurred with every fill up but i only get fuel from one place. maybe they have bad fuel.