I just brought a car which is an american brand car...and it costs much more gas than I thought, this should be a problem so I found some tips which helps my problem,and I post it out cause it may also be your problem.

1.Avoid rough roads whenever possible, because dirt or gravel rob you of up to 30% of your gas mileage.

2.Do not rest left foot on floor board pedals while driving. The slightest pressure puts "mechanical drag" on components, wearing them down prematurely. This "dragging" also demands additional fuel usage.

3.Keep windows closed when traveling at highway speeds. Open windows cause air drag, reducing your mileage by 10%.

4.Traveling at fast rates in low gears can consume up to 45% more fuel than is needed.

5.Drive steadily. Slowing down or speeding up wastes fuel. Also avoid tailgating - the driver in front of you is unpredictable. Not only is it unsafe, but if affects your economy, if he slows down unexpectedly.

6.Auto air conditioners can reduce fuel economy by 10% to 20%. Heater fan, power windows and seats increase engine load; the more load on your engine, the less miles per gallon.

If you got more, please tell me!