For proper Ultra sonic injectors cleaning take your car to Magic Motors in Model Town A Block. They will charge Rs 2000 for the complete ultrasonic cleaning of injectors by removing and cleaning them in ultrasonic bath machine. However, I suggest you to use STP concentrated injector cleaner for only Rs 340 for 150 ML bottle. It has good results. Mostly the Honda VTI and EXI models from 2002 to 2006 have 8 to 9 KM per liter fuel consumption in city driving so don't worry. Just replace the old spark plugs with new ones, change air filter, cleaned throttle body and tappets get adjusted, change fuel filter, use low viscosity engine oil like caltex 10w/30, do wheel alignment, fill tires air pressure up to 30 psi in all tires, change transmission oil as per Honda specification, change power steering oil with fresh oil and finally change brake oil with fresh one like Guard brake oil. Furthermore, do not run engine on idle for long time. On signals stop the engine and do not race engine uselessly. Do not use big size tires as they have extra weight and also have more drag. Use 185/65/15R.