I don't think it is the extra air but the oil that is in the air. K&N filters have oil and when air passes through the filter, the air will definitely pick up some of the oil. It may only be in the ppm range and some of this oil will deposit in the intake of the engine. So yes, I believe the K&N do make the IAC problem worse.
I do not have a K&N filter and I still have had the IAC problem. I run 6.5 quarts of oil and I think this is why my IAC gets plugged up. Also running a higher oil level can mean oil carry over into the cats and that is also bad. I wonder if my cats will go out and with my luck they will go out after 80,000 miles.
