Car was overheating slighty (little past half on temp gauge), using antifreeze but not showing up in oil. Car was slightly sluggish at first then lost lots of power, no going over hills. I have flushed raditor and changed thermo before the power loss in an attempt to fix heat issue. I am seeing oil in antifreeze, black crap but no antifreeze in oil, at least I am not seeing the chocolate milk oil. I did a compresssion test,120/120/160/160 so I thought head gasket. Pulled the head but I do not see any visible signs of gasket damage between those two cylinders?? Now I am concerned that I am chasing the wrong thing...lots of carbon buildup on valves in those two cylinders but I did see traces of antifreeze on the underside of the valve cover. The only time I have gotten lots of white smoke at exhaust is after I flushed the coolant system. The valves have lots of buildup so I thought about buying a rebuilt head and trying that out but now concerned this is not the problem. Does anyone know if this type of compression results could be pointing to a gasket issue? Is there something else I need to look into at this point. I don't know much about rebuilding heads so for me a rebuilt maybe better.