I recently bought a project car, the car blows some smoke. The owner said he thought it was the valve stems because it used to be only at start up. He said the car sat for awhile and now it blows smoke constantly. I pulled the throttle body today and the inside of the upper plenum is coated with an oil film. There is a hose coming from the valve cover (pcv?) to the intake, is that hose supposed to be there?