Well a problem surfaced with my 96 Cobra, explains the 6-K price tag. When the car is cold, on its first start I hear what I think is valve knock for the first 4-5 seconds of running. It almost completly goes away but if you have your head under the hood and rev it you can faintly hear it when the rpms drop back down. It seems to be comming from the rear passenger side head, almost sounds louder at the intake plenum. Do I need a valve job? I would like to work on the car myself, do I have to remove the heads for that kind of work? Any help would be greatly appreciated.