I can't tell you exactly what it is. What I would do right away, with any idle issue, is ensure you have no boost/vacuum leaks. Any small hose that is leaking can cause poor idle. That would always be my first check
and btw, you know how i said i dont think i would be able to quit smoking weed? well i havent since my surgery, and never have been happier and dont plan on going back to it either