Well I think I may have the dreaded head gasket problem. There seem to be very small white deposits at the head gasket by the #4 and #5 cylinders on the exhaust side of the engine. Here is a pic that I hope shows what I see. There is a white spot above and to the right of the #5 frost plug and a white line above the block heater at the #4 cylinder. What do you think?? Sean.