hello everyone ,, recently i have changed my car engine oil with shell , my car runs on CNG as well as Petrol(mostly petrol), after one day of changing oil , it starts a noise of like a diesel engine does , it showed it to 2 mechanics , one said ISS may sand gaya hy , i wonder sand kesay ja sakhta hy so two mechanics said to change the assembly block worth 30k ,, please tell my what should i do ,, , car itni b old nhi k ab engine ka ik part he change kar le ,,, mera doubt engine oil pe hy
please suggest me