My D16A6 is only burning oil when it is cold. When it is up to tempature you can hammer on it all day and not a drop is burned. What should I chase after first? Valve seals or piston rings? More specifically if you start it up cold and don't touch the throttle it is fine, then if you give it gas or start driving it before any tempature is showing it will burn, not too bad but noticble.