Does anybody else have anything to chime in with? I am at a complete total loss as to what the problem might be. I posted the snapshot that my code reader stored. Does anybody have any advice at all?

 

Either you have insufficient fuel being supplied to the engine or too much air.

If u have cleaned the Maf sensor (using maf cleaner), changed fuel filter(if it's never been done), checked plugs and coil packs (you said you had a scanner, you're not getting any misfires right?), checked your fuel injectors(unbolt the fuel rail and prime the engine but DO NOT START), and replaced all the dry-rotted hoses, then it probably is your intake manifold gaskets.

FYI the stock intake manifold gaskets are pieces of ****. Regardless of miles your truck is over 10 years old. It's probably time to do them. Hopefully the intake manifold isn't warped cause you'd have to replace that as well. You could have a compression test done relatively cheap somewhere.

I assume you've at least taken the plastic piece off the top of the throttle body right? (Not trying to sound like an *** just asking) You've cleaned the throttle body? (with a toothebrush)
You don't hear any abnormal rushing of air when you move hoses around? Just to be sure. Usually when it throws both codes it's because of a dry rotted hose/hole.

What about your exhaust manifolds? The cast iron manifolds heat up differently than the aluminum block and warp, or throw bolts, or just rust out. This happens directly in front of your 02 sensors and can cause the computer to say it's running lean. It would have to happen on both sides to throw both codes tho. Have you tried to clean your 02 sensors? (it takes a 7/8 wrench, they are difficult to get to with your average floor jack but doable if you take the tire and inner wheel well off)

If the stock iron exhaust manifolds are rusted out new stainless steel headers aren't that much more expensive. Just sayin

 

I know this thread has been on for a while, but I needed it today and someone else might also so here's what I had. '02 F150 Supercrew 5.4L that just started shifting the a/c from vents to defrost when I accelerated. Then 2 days later the service engine light came on. I knew it was a vacuum leak from past experience with another car. I found mine to be a small connector piece at the firewall behind the battery. It's a t-shaped connector and the hose connector piece was totally dry-rotted. After I messed with it, the service engine light came on. I also noticed the hose from the top of the intake manifold to a green plastic elbow on driver's side firewall also very much dry-rotted. I replaced them both for a total cost of $3.47. I personally think it was the @2" connector piece by the battery causing the problem, but I was already there and doing both only made sense. I reset the light by unhooking the battery for 2 minutes. Engine runs smoother, no light, and no shifting air when I accelerate. I was able to feel the elbow behind the PCV and it felt fine. Both pieces I replaced are right on top and easily accessible. The only thing I had to do was remove the 5.4L Triton cover using a 10mm socket (3 bolts). Took 5 minutes. Hope this helps someone.