I really wanted to flush the myvi i am driving. Its 12 years old. Engine is fine without any weird noise or oil burning problems. But there is a leak that is common in myvi of this generation that is the housing seal that connects from engine to the oil filter. Even my mechanic does not recommend me to flush for simple reasons that a lot of seals are worn and might be corroded further and cause more leaks from other places if aggressive detergents is used.

Because it takes time and money to change all those things. Its not just the rubber seals. The adage "if it ain't broke don't fix it" comes to play here.