I have a Nissan Pino 2009 model. It has clocked 162000 on the odo. I was also having the same issues.
So got a complete tune up which includes:
1. Spark Plugs replacement and setting the gap according to the Engine Manual.
2. Catalytic converter cleaned.
3. Throttle body cleaning.
4. Used Liqui Moly ceratec mixed with engine oil (that has reduced the engine noise to quite an extent).