I don't know about the 2009 model, but let me give you some insight to my 2006 Expedition, 5.4 3V Triton.
I bought it new in '05 I have 74K miles on it, and recently had the error codes P344 and P340 come up. Swapped out the cam position sensors, light still there. Had my local Honda mechanic check it out, he noticed my positive cable in bad shape (I had a hose clamp on it, because the bolt on it broke). He swapped out the cable ($262, just the part).
Error code still there, took it to a Ford dealership, they said the TSB instructions for testing the alternator was the problem. They replaced the alternator ($486, just the part), light was still there.
Their next diagnosis was that the PCM is bad ($919, just the part) that they have on backorder and apparently no one has.
Since they had promised that the alternator would fix the problem, and it did not. I had them put back my old alternator and paid them the $119 labor charge for pulling the codes, that I already knew.
So now, I can't smog the car (I'm in Cali), and can't fix it either... if in fact the PCM is what is bad. The messed up part about the whole thing?
It idles smooth, shifts smooth, no symptoms whatsoever of it having a problem.