Hyundai Other Engine Poor Mileage

U Had Bought Ma Hyundai Xcent Before 3months. Last Month I Had Ma First Service. After The Service Ma Mileage Is 12 . Before I Used To Get...

I Realized An Increase Of Fuel Consumption For Example By 20 L. ( 5.283 Galon) It Goes For 118 Mile , But Now It Drives Just For 37 Mile...