Automobile Forums  Where Car Enthusiasts Go to Discuss Cars Online

I have 2010 sebring chrysler. The problem is when I driving say around 45mph then I release the padel the speed starts dropping then around 40mph it maintains that speed for 5 seconds then keeps dropping slowly.when I driving in freeway I need to have a good distance from the other cars in front of me becuase cars start breaking when there is traffic I would start breaking and release the pedal my car would catch up the car in front of me and need to start breaking harder.My RMP looks normal.I have to mention that I have seen it one's the RMP moving up and down little thats when I release the padel. I have clean the throttle  same problem and nothing lights up on by dashboard to tell that something is wrong.Does anybody know what could be the problem. thanks