Dear community, my rolling living room (Volvo 850 year of construction `95, petrol 2.0 10V (no turbo), 240.000km) unfortunately tends something to the oil consumption (0,8-1,0L/1000km) and emits blue clouds. After all kinds of research I first tap on the valve shaft seals, second on the piston rings. But I can not get it out quite clearly, therefore I would like to describe the symptoms and maybe you can give me tips where to reach first (or there are still other probable possibilities?). In cold or lukewarm condition there is nothing to see, no smoke. Ok, water vapor if it is cold, but that seems really ok to me. Only if the engine is nice and warm the thing comes to mind. And indeed after short idle time (from 10s) and following gas shock or after mountain descent in the sliding operation. Then smoky short blue and then it is good again. Probably everything is repeated at any time. Otherwise there is nothing to be noticed. Black soot is naturally inside in the exhaust. During the empty run or normal ride, there is nothing to notice. Then you should have taken the oil with your car.