I cleaned my throttle bodies for the first time, I had read all the threads and thought Id check it out. When I opened my airbox I thought I was wasting my time, there wasnt any oily residue on the bottom of the box and the throttle bodies werent discolored much and didnt really wipe anything off with my finger. I went ahead with the cleaning since I was already in there and put it all back together. I had to lower my idle after the cleaning(Id raised it yr before last,but forgot I had to)and it seems to have smoothed it out. I will make that a once a yr service now.