Kia Rio Engine Poor Mileage

I Cleaned The Throttle Plate, Checked Air Filter, Got The Oem Ngk Laser Iridium Plugs, And I Still Get Poor Mpg. I Checked The Gap On The...

I Bought This Car Used A Few Months Ago. Warranty Is Almost Up. I Took Good Care Of The Car, And Previous Owner Car Maintenance Records. I...