I did a search on this subject & it seems extensive. I have the problem in drive , while warm. it will idle at 550rpm stumble slightley like it has a mild cam than jump to 800-1000rpm's & than back & so forth. I cleaned out the TB, IAC, new gaskets, Cleaned EGR. Still surgeing but not as bad as before . Also how long does it take for the pcm to relearn idle

 

ttt

 

check out some of the other hesitation/idle posts.. its very common and very hard to diagnose/fix from what ive seen.. and i have the same problem that you do..