For a couple of months now my 240 has been idling strangely. Generally on a cold morning it idles at around 1400RPM initially, but idles high, anywhere from 1200 to 1500RPM even after being at normal operating temperature for sometime. During the middle of the day it idles fine, about 900RPM, or less and rougher now after i adjusted the idle screw to try and get the morning RPM down. Is it possible that the outside air temperature would be affecting my idle speed? Is there a component that should automatically adjust the idle speed for air density or something like that? I though that it could have been my accellerator cable sticking but tapping the accellerator doesn't make any change to the idle speed. Any ideas?