yea bro its your iacv (idle air control valve) i had the same problem with my crx. my idle kept idling around 2000rpms n than go back down to 1500 and than back to 20000 and than 1000 and than 2000 but not consecutively it would stay at one for about 2-3 seconds n than change n stay at another rpm for 2-3 seconds n change again. so what i did was looked up some threads on it and found that if u clean the iacv than it will stop doing that. I cleaned mines and it doesnt bounce around anymore. it will idle at 2000 when i start it and than go back down to 1000