thank you for answer.
why I wanted to hear your answer: I understand those sparks a bit, but THIS ENGINE IS CONSUMING ABOUT 0.5-0.8 LITERS OF OIL IN EVERY 1000 KM. that means my problem is turbo oil seal or exaust valve steam oil seal? I think this way, because if such amount of oil is burned in cylinder, sparks should have sludge or carbon on it?
thank you in advance!