This is in regards to your query posted on the website CarDekho.com, we would like to inform you that Hyundai i20 petrol is the best option in its price range. Hyundai i20 1.2 liter petrol gives mileage of 14.0 kmpl in city conditions and 17.0 kmpl on highways.
Other cars available in the same price range car be Maruti Swift petrol and Volkswagen Polo petrol. Maruti Swift comes equipped with 1.2 liter petrol engine, it gives mileage of 12.8 kmpl in city conditions and 16.6 kmpl on highways. Maruti Swift can be a good alternative as its maintenance cost is low, resale value is good and it has got strong service network.
Volkswagen Polo petrol is powered by 1.2 liter engine. The mileage of Polo petrol is 12.5 kmpl in city conditions and 17.0 kmpl on highways.
You can use the given link to view Comparison of Hyundai i20 Sportz, Maruti Swift Zxi and Volkswagen Polo petrol Highline.
Initially, Hyundai Elite i20 Magna comes with a petrol and diesel engine but a CNG kit can be fitted with the one which has petrol engine. You will have to sacrifice with power to get more fuel economy and if you convert a petrol car into a CNG car, you may loose the warranty on the car and resale value of CNG cars is lesser than petrol cars. It is always recommended to get the CNG kit fitted from the authorized service center so that you can avail the warranty services as well. Moreover, the performance will depend on how the car is driven and maintained.
Click here to find the nearest Hyundai service centre by selecting your city in the drop down list.
How much fuel goes into a car varies on a lot of factors. Now you haven't mentioned how many km did you drive post the low fuel warning light as that could also determine how much fuel goes into the car. Even though the manual says that the tank capacity is 45 litres, the amount can vary by a small margin, give or take 2 or 3 litres. Also filling fuel in the hot day or in the night also makes a difference considering fuel expands during the hot day and contracts when the temperature is cooler. All said and done, make sure you fuel up within 3 to 4 km after the low fuel indicator light pops up.