ok a few weeks ago my t-stat went and my car over heated. ever since its idled much higher than it used too. i start it and its between 1500 and 2000. then after a few seconds it drops to 1000 and then to the normal 500-600 area. when driving the car at operating temp it does the same thing whenever i push in the clutch. i kno i have a bad o2 sensor but it was broken before this problem came along. i have done a search in many of the forums and i cant find a thing. please help me out i wanna get her runnin right even tho shes gettin tpi this winter. help please