Hey guys I have heard of this problem a few different times but can recall how to fix it. My Idle goes up and down between 1000-2000 rpms until the car is warm then sometimes while driving. I guess maybe the car cools off and starts idling funny again. I have check coolant level it appears to be find and my overflow is filled between lower and upper. ( heard that helps sometimes) SO I need some detailed instructions on how to fix that. Please let me know thanks.