my motor is a stock Y7, and right now what it seems to be doing is when you first start it up it idles fine. Then after about 30 min of driving the idle will drop lower. not sure what RPM cause I dont have a tach. but i have asked alot of people and they have no idea. and its not when its cold and you start it and it idles high untill it gets to temp. It does it during hot and cold.

 

have you checked the iacv?

 

I will try that and see what happens