ford triton whats normal fuel pressure?? help

[melmount]

I have a friend that has an 02 expedition, can someone tell me what fuel pressure readings are supposedto be? has a lean condition but i want to check fuel pressure? cant google and get an answer? need to know pressure rating?
thx

[dalton1]

I think its supposed to be about 50 psi, lean codes will also be caused by a bad mass air flow sensor.

[melmount]

i read that. I found the pcv valve out o the valve cover. Still in the hose but not plugged in. Also seemed valve insides went bad. I put the pvc valve in the cover but plugged the hose. No vacuume leak anymore.(i hope andd assume) She's picking up a valve soon.
I had code po171 and p0174 lean banks 1 and 2. I thought maf too. It looks like it needs to be cleaned. I checked it out at her work. I had no cleaner there. I think the pvc will fix it
thanks

[Robsr]

Fuel pressure spec is 30 to 45 psi. unmetered air entering the intake such as an unplugged pcv valve will cause a lean codes.