In reality a performance shop should be able to see what A/F ratio is at WOT.
Alot of things can be ruled out by that.

Things you can check yourself:

If you have a aftermarket intake,check for oil being drawn in.I clean mine every oil change.

Clean off the maf with a quick evaporating cleaner(adv carb cleaner is more like wd40).

Like smoke show said,change the fuel filter.

Any misfire like a cracked coil would throw a code.But you might aswell check your plugs and coil to rule that out.With up'ed boost I hope you went with a colder plug.