AOA, friends. I have Honda City 2007 idsi. Had an issue with engine oil couple of months back, as it was showing at minimum level and sometime empty. The Machanic says to change the assembly. No leakage of oil no nothing. Don't know what causing the problem. The mileage on petrol is 670 per tank (no cng instal). No issue of fuel consumption. But one thing every morning when I start it a mixture of water and black oil blows out from cylencer. Should I go for assembly change or need other things to look for too. Machanic says it will cost me 15k for the assembly. ( assembly japani, not Thailand, Machanic says).