hey im picking up a dc4 in a couple of days (2 to be exact). i was wondering what is up with a car when its idel is at 1000 and go to 2000 like a person is reving the car. i was planning to get it as a project car for my future daily driver. (turning the car back to stock). the idle stop after like 5 minutes and then when i drive it and stop it happens again. someone said it was a sensor in the manifold? is that it? how much would it be?