Since i bought my 98 Prelude last fall i have never driven it in warmer weather til about a month ago when its actually been hot out. The car runs well but since its been hot the idle sits a little low, around 400-500 once the car is at operating temperature. Also when its hot out the temp gauge seems to sit slightly lower than the normal spot, and thats when the idle tends to be low. Now in the mornings when its still cool the car idles nice, even at operating temp, and only when its cool out the temp gauge sits at its normal spot.....weird. I have been meaning to get at my IAC to clean it out but this almost sounds different than it being that, however i think ill clean it anyway. You think this sounds like a coolant/thermostat thing? Could it really affect the idle? A flush perhaps... Any input would be appreciated. P.S i have replaced the cap/rotor and plugs just to rule out that.