From what I searched if it was a leak it would do it all the time, But when I first start my car in the moning is starts idling at 2k, and after 5 mins it slowly drops to 1, and in a matter of seconds is going for 800 to 1200 up and down up and down like crazy I dont have a clue what the problem is. I have a b16 if it helps

 

I would say its probably your IACV because your FITV is what makes the idle high while warming up and then the IACV takes over to control air flow (Idle Air Control Valve)
try this website
it's a great idle trouble shooting guide

http://www.ef-honda.com/ben/

look under tech and then bad idle trouble shooting.

I ended up cleaning my IACV and adjusting my idle and she runs smooth as silk.

Good Luck!