Hi there,

got an 04 f150 fx4 5.4 3valve,

Throwing code p0191, been on the website last few days reading all the issues with it,

have replaced the fuel rail pressure sensor

have replaced the fuel pump driver modual behind the spare tire,

Fuel filter replaced with in 3000miles.

Problem still occurs, the EDGE program reads 40psi at idle, on the FRP but when in demand fuel pressure drops to 11 - 8 psi and engine acts as if it were stuck on a rev limiter.

Is there any last options to try before the trip to the stealership??

Thanks in advance

Jeff Stewart

 

Fuel injector clearner was done at the 3000mile fuel filter change.

 

Maybe a clogged sock filter on the fuel pump inside the tank?

 

i bet its a fuel pump going bad on ya

 

Run stock tune. Still there? Run stock tune, factory intake.

List all mods.

 

hello dear
how your problem was fixed i am in same boat i replaced fuel driver module all injectors fuel pump is arround six months old problem was fixed when i changed pump last time but again it started