Jazak Allah dear. Before all these activities, my Belta was giving me 12Km/L and one more thing that I have done is that I have filled my car tank with 10 liters of Hi Octane and rest of the tank with Super. After all these changes I am expecting it to give me more Km per liter and better performance.
For BMW horn, if you are unable to find it in ur market then let me know, I'll bring it for u cuz I may visit Rawalpindi by the end of this month or mid of next month. I installed Pakistani BMW horn which cost me Rs.1,500/- and original BMW used horn is around Rs.3,500/-