A similar thing happened to me on the way home from work about a month back. I assumed the turbos were completely down based on how it was driving. No CEL, not sure about codes. Next trip the power was fully restored, so I never hooked up a code reader. No problems since. I thought maybe it was bad gas, so I babied it until I turned that tank over. I did find some other posts via google with reports of similar behavior. Maybe an obscure bug or hardware hiccup as previously mentioned. But my problem cleared without need of a reflash.