Fuel pumps break down when cars running on CNG and the electronic pumps keeps rotating continuously, sometimes in the Blank fuel tank, resulting in Motor heat-up and its waisted, Buy any Fuel pump, but do fill your tank with some 10 to 15 liters of petrol atleast, then do turn it on Petrol once every day and you ll prolong your pumps life. If the No. 2 (local, chinese etc.) pump is less than Half the Price of genuine then you should buy that, otherwise go for the original one but in my observation, the genuine will fail too if you keep on running on CNG with Blank fuel tank