any solution for it..

There is a good chance that the engine is full of sludge from using improper oil or other factors. Watch your coolant level, as well. You can de-sludge the engine with Amzoil crankcase cleaner. After that, use either Mobil One 0W-40 or ELF oil made to meet mercedes specifications. If you have been going to local quicky lubes where they use bulk oi, you have been making your own problem. Most of these oils meet NO auto makers specifications. They are cheaply made and produced to keep costs low at the quicky lube. You should also try to de-sludge your intake manifold with Gum-out spray applied to a vacuum port. With the engine running, it should clear any sludge inside the PCV hose or PCV system. Many foreign car engines are vulnerable to sludge formation due to the fact that they were engineered to run at high autobahn speeds. Driving them like they are wimpy can cause premature sludging. These engines are like athletes and need to be exercised! NEVER use anything in the cooling system but genuine MB coolant (yellow). There is no such thing as universal coolant, or even universal oil. Good Luck!!