Go On A Diet
For every 100 pounds your car loses, your car's gas mileage improves by about 2%. Put your car on a diet and take out all unnecessary items out of the trunk. Keep what you need in your car to only the essentials. Try to make a habit out of this and clean out your car periodically. It's easy to forget over time and let your car get fat and heavy with things you don't need every day, like golf clubs, books and water.
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