Thank you Soiled. In the tune up, I have changed all oils with engine oil Mobil fully synthetic 5W-30. Oil, fuel and AC filters, All spark plugs with Iridium IK 20, timing belt and drive belts and bearings. MAF sensor, throttle body and fuel injector were cleaned. Wheel alignment and balancing were performed. Tyre pressure is 32 with Nitrogen. Fuel is Octane 95. One of my friend told me that, if we drive MAF disconnected we can have an idea. If there is no change in performance the MAF is not functioning and if it is improving the MAF is malfunctioning like. Traffic also heavy in Colombo. I am not too heavy foot in throttle. Now I hqve planned to change a new MAF. I have purchased one Original OEM Denso MAF sensor from ebay from a US seller. This costed me a USD 150. Because I am too suspicious on MAF. Coz, it is 14 years old and my mechanic did not use the proper MAF sensor cleaner. I do not know what he has used. I heared, it may go wrong with the improper cleaning too. It s better to change. Do I have ti reset the ECU once I change the new MAF? How can I reset?