Adjusting my IAC is on today's to-do list. The bad thing about adjusting things on this is it has to be up to operating temp every time before you can do anything and with all this aluminum crap it takes forever to get there. I was looking at some of the software this morning and there is an area for decel fuel adjustment. This might be something that will help. The specs say that when you take your foot off the gas the fuel is cut off. Maybe in my case I still need a bit of fuel to flow even after I take my foot off. It seems to make the difference when I do it myself and disengage the clutch.