bad fuel pump?

[mycool]

So i have noticed when i first fill up my tank ie. relieve the pressure in the tank opening the cap and i start to go to give it gas it hesitates and acts like it has no power then will pick up and go again. i am also gettin codes p0171 and p0174 with the bank 1 and 2 being lean. changed the plenum gaskets and fuel filter. thinkin it could be O2 sensors or perhaps the MAF maybe even the fuel pump... i am at a loss and it is driving me nuts

 

[Dan Whitaker]

I would say the injectors or maybe the fuel pump regulator.
Usually a fuel pump just quits.

 

[Studious]

So i have noticed when i first fill up my tank ie. relieve the pressure in the tank opening the cap and i start to go to give it gas it hesitates and acts like it has no power then will pick up and go again. i am also gettin codes p0171 and p0174 with the bank 1 and 2 being lean. changed the plenum gaskets and fuel filter. thinkin it could be O2 sensors or perhaps the MAF maybe even the fuel pump... i am at a loss and it is driving me nuts

2 possible things in my experience.

I had the same problem a few years back and figured it could be my fuel pump. Talking to the guys at my local ford dealer they gave me a few ideas.

They told me to get under and softly hit the bottom of the gas tank with rubber mallet. It is possible the little sensor and 'floater'(lack of the right term) could be inverted or hung up in the back of the tank. That worked for me. Years later it still works fine.

If that doesnt work, its possible that a fuel injection sensor or an oxygen sensor is failing or in the . However, if it only happens after a fill up, I could be wrong.

Im not a certified ford tech, but Im happy to add my 2 cents!