You can try to take the
part off and clean it thoroughly with Carburater cleaner. The idea is to clean the carbon buildup from the valve body. My truck woke up one day and decided it didnt want to idle at all. A tow truck later, then delivered to the mechanic, it started and ran normally. He diagnosed it properly as the IACV. He said it is common and the jolting of the tow truck is sometimes enough to loosen the carbon. Once I got it home, upon advice of the mech, I took it off and cleaned it and saved myself 150.00. It worked. 4 years later, it is still working fine, although I think it's time to clean it again. The other morning it would not idle. I used the trick he told me previously, " if it ever does that, tap on the valve with a screw driver. It will loosen up the carbon enough for it to idle. So I know I'll be pulling it again and cleaning it this weekend.