The state I live in - California - is averaging the highest gas price per gallon in the continental U.S. these days, according to the Gas Price Chart available on GasBuddy.com where you can check out the average gas of your area down to the county level. As the price at the gas pump rises steadily exceeding $4.25 per gallon in my area as of May 2012, I'm all into knowing ways to save money on gas.

There are some general ways to save on gas usage - by driving less or carpooling more, whenever possible. To drive less, try to combine multiple grocery trips into one with better grocery shopping planning ahead so you don't waste gas by doing more in a single trip. When you carpool with someone else, you're also saving gas on a per person basis.
If you absolutely need to drive a car, consider to review your driving habit (I know it's kind of very hard) as it will affect your gas mileage per gallon. The optimized speed for the maximized highway MGP depends on the model of your car. However, in general, if you're on a highway going over speed limit, you're absolutely not getting the best MPG and may be off by five percentage, ten percentage, or even more. It might be too trivial to remember the exact speed to drive for getting the best MPG, but if you can reduce aggressive speeding and don't drive over highway speed limit, which you shouldn't anyway, you'll be stretching your gas mileage in the right direction.
If you absolutely need to drive a car, consider to review your driving habit (I know it's kind of very hard) as it will affect your gas mileage per gallon. The optimized speed for the maximized highway MGP depends on the model of your car. However, in general, if you're on a highway going over speed limit, you're absolutely not getting the best MPG and may be off by five percentage, ten percentage, or even more. It might be too trivial to remember the exact speed to drive for getting the best MPG, but if you can reduce aggressive speeding and don't drive over highway speed limit, which you shouldn't anyway, you'll be stretching your gas mileage in the right direction.

If you tend to do brisk acceleration, stop doing that. Some people say you may be able save a gallon of gas a week by not doing rapid acceleration on the road. A test shows the difference in fuel consumption between slow acceleration and brisk acceleration may not be that much unless you're driving a hybrid, but avoid the possibility that you will need to brake does help a lot in terms of saving gas.
Remember to keep tires properly inflated. If tires are under inflated, they may cost you up to 4% of fuel efficiency according to U.S. Department of Energy. On the other hand, over inflated tires may increase blow out risks. You want your tire pressure to just about the manufacture's suggested PSI (pound per square inch) which is available on the sticker on the driver's door side. I recommend using a non-digital air pressure gauge (e.g. a Handheld Dial Tire Air Pressure Gauge) for measuring tire pressure. A non-digital air pressure gauge does not require battery thus it is always ready for measuring tire pressure when you need it. Besides, non-digital air pressure gauges tend to cost less than the digital ones. American Tire has an online Tire Pressure Gas Mileage calculator that tells how much is low pressure tire costing you.w
Lastly, evan you can't possibly avoid using gas, consider this: When I pay at the pump, if I chose to pay with a credit card, I always opt for using the card that gives me some money back on gas purchase. For example, the AE card I have gives me 3% cash rebate on every dollar I spend at any gas pump. You may consider the same approach because every little bit of saving counts.
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by Charles Gwa
Remember to keep tires properly inflated. If tires are under inflated, they may cost you up to 4% of fuel efficiency according to U.S. Department of Energy. On the other hand, over inflated tires may increase blow out risks. You want your tire pressure to just about the manufacture's suggested PSI (pound per square inch) which is available on the sticker on the driver's door side. I recommend using a non-digital air pressure gauge (e.g. a Handheld Dial Tire Air Pressure Gauge) for measuring tire pressure. A non-digital air pressure gauge does not require battery thus it is always ready for measuring tire pressure when you need it. Besides, non-digital air pressure gauges tend to cost less than the digital ones. American Tire has an online Tire Pressure Gas Mileage calculator that tells how much is low pressure tire costing you.w
Lastly, evan you can't possibly avoid using gas, consider this: When I pay at the pump, if I chose to pay with a credit card, I always opt for using the card that gives me some money back on gas purchase. For example, the AE card I have gives me 3% cash rebate on every dollar I spend at any gas pump. You may consider the same approach because every little bit of saving counts.
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by Charles Gwa