general problems of the 2003 Hyundai Santa Fe

The vehicle for the last 3 years was not getting the gas mileage suggested by manufacturer. It was taken repeatedly to dealer where we were told, "everything checked out just fine". All maintenance was done as required by dealer". As car became more sluggish and finally quit running altogether- we took it to an outside mechanic and learned that the catalytic converter had gone bad. I checked the internet and this is a common complaint with this vehicle- dealers are repairing transmissions and emission controls and customers are still complaining about bad gas mileage, sluggish vehicles. Now that the catalytic converter has been replaced- the car is getting the correct gas mileage and running better.