your lean codes is from additional air coming into the engine from somewhere. u have more air than fuel. thus causing your lean code. first thing i would do is to check for vacuum leaks and then make sure the maf is clean. reset your pcm and if it comes back on have your O2 sensors monitored to see if they need to be changed.
just from alittle bit of experience from working at ford.
Are you leaning at part throttle-full throttle? When did it start? After chip or maf change? Could be calibration issue w/maf/dirty maf? Have you checked fuel psi? Fuel filter? Injectors dirty? Need a little more info to help w/diagnosis.
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