I would focus working on the codes 1st, the reduced power mode is to protect you + truck.
The computer detected a problem, and put the engine into a reduced power mode.
A drive-by-wire system with a bad signal could cause a reduced power mode. The electronic signal from the gas pedal to the electronic throttle body was lost.
After checking for unmeterd air leaks on your Intake, Pcv, and Egr systems, need to clean
MAF/IACT sensors, and reset codes.
If this doesn't fix the problem:
1) Get a professional smoke test done, for unmetered air leaks.
2) New MAF/IACT sensor
3) New Upstream H02 sensors.
www.youtube.com/watch?v=FfiQ7qWiG-M
or
Do a Google ''Youtube DIY Auto Scotty cigar'