Yup its the fact that u r facing the mileage of 1000cc vitz is 8 to 11km/L
no doubt "1.0 L 1KR-FE I3" is very efficient Engine but the real problem is our low grade Fuel which is not compatible for that.
1.0 L 1KR-FE I3 mostly make knocking, vibration, low mileage, is only way is to get 1.3L vitz,