Lean Issues Read Entirely

Hello I'm Nicholas I am from Commerce Georgia I have a 1998 Ford Expedition Eddie Bauer 5.4L 4X4 with Mach Audio System

In some category's I am smart in other places I am not and I would like to help others with issues and have conversation but I also have a issue also and in need of some advice !! Please Help

I bought my truck in March of 2013 I had a XLT previously now I have the Eddie Bauer 5.4L when I bought it the man said it needed new Exhaust Manifolds and Exhaust Manifold Gaskets he had both. So I took it to a local shop He called me a day later and said he accidently broke the Exhaust manifold bolts into the head I told him to drill it out and put a bigger bolt in no problem well he "accidently" broke the ears off of the head so I had the truck towed somewhere else to another shop I bought New Heads Water pump since it was going to be accessible Head gaskets intake and exhaust gaskets the gaskets came as a set with the entire top end as far as gaskets go Well Now a year later it is still showing CEL: System Too Lean Bank 1 P0171 System Too Lean Bank 2 P0174 mostly it shows up P0171 when it comes back after erased What I have done is Ive Raplaced the Faulty PCV Valve and line and Both Elbows I have also Taken The MAF ( Mass Air Flow ) sensor out and cleaned it with MAF cleaner runs ok for about a month and CEL illuminates again Fuel Filter has been replaced the Fuel pressure is around 40 I cant Remember I know its a pound or so off but not enough to make it run rough and throw codes
air filter has been replaced also ummm Any questions ask Please I insist !!!

Sorry if I shouldn't have posted this a Admin or moderator can move to the right place if they like would like !

Thanks in Advance Nicholas

Diagnostic Trouble Codes (DTCs) P0171 bank 1 (Cylinder 1) and DTC P0174 bank 2 indicate the fuel/air ratio is too lean. The fuel trim system is at the rich correction limit.

DTC P0172 bank 1 and DTC P0175 bank 2 indicate the fuel/air ratio is too rich. The fuel trim system is at the lean correction limit.

DTCs HO2S Reference list:

HO2S-11 = DTCs P0171 and P0172
HO2S-21 = DTCs P0174 and P0175
Possible causes:

Fuel system

Excessive fuel pressure.
Leaking fuel injector(s).
Leaking fuel pressure regulator.
Low fuel pressure or running out of fuel.
Contaminated fuel injector(s).
Vapor management valve (VMV) leaking.
Induction system

Air leaks after the MAF.
Vacuum leaks (vacuum lines and gaskets).
Restricted air inlet.
PCV system.
Fuel purge system.
Improperly seated engine oil dipstick.
EGR System

leaking gasket.
Stuck open EGR valve.
Leaking diaphragm.
Base engine

Oil overfill.
Cam timing.
Cylinder compression.
Exhaust leaks before or near the HO2S(s).
Check intake air system for leaks, obstructions and damage.
Check air cleaner element, air cleaner housing for blockage.
Verify integrity of the PCV system.
Check for vacuum leaks.

Change the O2 Sensors also you may want to clean the exhaust ports thru the throttle body

This list should be a sticky. It would answer the same question posted week after week after week...

I have Checked everything already fuel pressure o2 sensors fuel pressure regulator purge and I just changed the EGR valve gasket and pipe today Im going to try and do another Smoke Test to see if I can Find another leak