high idle gas smell

ok,this is for a prelude, but no one usually answers me under that forum so i wanted to try posting here...thanks i have a 1990 prelude, SOHC engine 5speed. Anytime i start this car up, it idles pretty high, usually between 2000 3500 rpms. it does this for about 5 minutes then stops. even if i start to drive before the idle reduces, it still pulls hard and when i push the clutch in the idle shoots up. anyone know what this could be. if i start the car up after its already been ran a while, and its still warm, it does not do this... i also get fuel fumes in this car but only when my sunroof or windows are open, but no leaks that i can find? any suggestions on that? thanks