Every once and a while when I am going down the road and go to shift the rpms stay and sometimes rise up. For example if I push the clutch in while im in thirrd at 3,000 rpms the rpms stay where they are and sometimes rise up(my foot is off the gas). Its not the normal rise up. I know usually they go up a hundred rpms or so but this will go up a few hundred and will stay there for a few seconds. After that it doesnt come all the way back to 700 rpms like usual, instead it drops down to about 1100 and idles there. Is the IAC sticking?