I had the same code before I did my UIM/LIM rebuild. The EGR passages were clogged/filled with oil/carbon where the TB meets the UIM. I am still waiting on parts from the dealer to finish mine, but take the TB off and clean the passage and back side of the TB, as it will be probably look nasty. If the passages were as clogged as mine were, the rest of your UIM/LIM probably looks the same, especially the LIM.