Do you have anymore details? year, model, engine? Have you, or anyone else edited the pcm besides Nelson Performance?
This is part of a post from Chris at HPTuners related to this code:
"Our competitors often see this problem when you go messing with various ETC related tables that control the operation of the ETC. The TAC runs its own tests to verify operation of the ETC. In some cases this can permanently disable your PCM, hence why we won't ever add those tables.
I don;t think the PCM holds the answer to your problem"
Anyway check out this thread:
u0107 and reduced engine power - HP Tuners Bulletin Board
Post up all the details or we will be of little use to help out.