i just had this on the missus frst took the head off thinking it was gonna be the gasket but found it to be 2 cracks between the valves on the middle 2 cylinders. but the smoke on this one only happened once the car had warmed.. not cold.. but also had similar problem with an inlet manifold gasket leaking through the waterway into the ports... the garage tested this on the meter said H G gone but i just changed inlet gasket and all was fine..