I have this problem for a couple of weeks. When I start the car, the engine goes to 1500 RPM and then gradually to 2000 rpm. Stays there for about 30 seconds, then goes back to 1600. Then, funny things happens. It goes to 2000 immediately, then 1600 immediately, then
2000, then 1600, after about 10 cycles, it goes back to under 1000 and then to normal (about 600 rmp). Today, things got even worse. It stopped at 2000. I waited for 5 minutes and it never went back. When I turn it off, I heard strange sound never hard before. It sound like something stop slowly after I turned it off.Any ideas?
Thanks,