Cirrus,I hate to say it but I think you nailed it. I did not have the time to tear into it so I had my mechanic tear into it. At first we thought it was the head gasket. My wrench man has never seen this problem before on the G54b motor.He said you cold stick your finger in the head and feel a stream coming from some where on the top section of the head. I had a even 200 lbs in all cylinders.I am sure its a defective head. I am going to have the head pulled and if its defective I hope clear water stands behind the head. Less than a year and 6k mile since the rebuild I have snapped one of the studs on a timing chain sprocket gear and know the possible defective head. Oh well I am getting to know the pros n cons of the G54B motor more then I want. <img src="/forums/images/graemlins/barf.gif" alt="" />