I was having a similar problem. Mine ended up being a wire shorting on the coil pack harness.

 

even with the key on engine off it says reduced engine power when I push the pedal to the floor, I can drive the truck down the road to about 30mph but while getting there the trans shifts really quickly and very smoothly. I do have a slight miss and im getting the p0300 random misfire code so I might be having the same issue as you. could you provide me with more detail on which wire it was and were it was shorted at?

 

Mine was on the #3 coil pack wire. You will probably just have to take off the complete bank of the coil harness and look everything over. Also, check that you don't have any bent or broken pins on the coil pack itself.

 

alrighty thanks man sound like a good place to start, I have another question...could a going bad neutral safety switch be a probable cause of this? the housing was burnt in the fire but for the most part looked intact and it still indicates the gear I put it in but that was the only thing I didn't replace that was damaged in the fire

 

ive come to realize that my neutral safety switch is burned up pretty bad from the fire, and its the only thing I haven't replaced since the fire....Could that possibly be it?

 

ok ive replaced neutral safety switch no luck.... I also replaced map sensor seeing how I was get a maf performance code and know that a bad map sens can sometimes make it look like the maf sens is the culprit but still no luck.....I can unplug the maf and the engine idle doesn't change on throttle hesitation, now keep in mind that it still says reduced power With the ENGINE OFF AND KEY ON....I have yet had anyone explain how a sensor or what sensor could cause this....Im going to buy a new maf when I get paid but If anyone and I mean anyone can help with this I would greatly appreciate it.