Has anyone had a problem when they start their ls1 up, that it automatically revs on its own at idle? I have a 6 speed, and it fluctuates between 1700-2000rpm on its own when I start it up. I tried revving it myself to see if it would fix the problem and it revs up to 3,000 and holds there until I cut the car off. It makes me nervous to drive it in case it gets stuck while driving. Any ideas as to why?