Mythbusters: It's a Gas
Are you drowning under the burden of high gas costs? If taking public transportation isn't an option and you have no immediate plans to buy a hybrid vehicle, is there anything you can do to save gas?
The truth is that the way you drive, the health of your car and your lifestyle all play a part in fuel efficiency. But there are a lot of myths out there, too. We talked to the experts to get to the truth.
Can you save gas by driving at lower speeds?
Aggressive driving reduces fuel economy by as much as 33 percent at highway speeds and 5 percent around town, according to Fueleconomy.gov. "Avoid aggressive driving," says Troy Green, spokesperson for the American Automobile Association (AAA). "Keep the speed limits in mind and avoid sudden starts and hard breaking." Syndicated car columnists Tom and Ray Magliozzi, also known as Click and Clack, state the obvious: "Drive less and walk more." They add that if you must drive, "Drive gently."
Does idling impact fuel efficiency?
Experts agree that excessive idling wastes fuel, and areas that encourage idling like restaurant drive-thrus should be avoided altogether. "Avoid excess idling whenever possible. Go ahead and park and go into the restaurant. Even when you pick children up from school, find a parking space rather than needlessly idling," says Green.
avoid using the air-conditioner when
driving on the highway?
It is fuel-efficient to drive with your windows down if you are driving in your neighborhood at 25 miles per hour, says Diane MacEachern, author of "Beat High Gas Prices Now!" But if you're driving on the highway, "keeping your windows down creates drag on the car which slows the car down and the car uses more gasoline to gear it up to highway speeds," she says. MacEachern also recommends switching off the air conditioning, radio, lights and windshield wipers before turning off the engine, so that they don't come on automatically when you start the car. This improves the overall efficiency of the car, she says. Goss adds that this is only true for cars that are more than 25 years old.
Is hypermiling a gimmick?
Hypermiling is a driving technique aimed at getting the highest possible mileage out of a vehicle. Some examples of hypermiling are coasting instead of braking and optimizing your route. Although the practice is gaining popularity, some hypermiling methods can be extremely dangerous. Automotive expert Pat Goss says drivers should avoid drafting, which involves getting as close as 4 feet behind a vehicle to take advantage of the wind resistance on your car. This creates a safety hazard in case of a sudden stop.
Another dangerous practice is driving up to the speed limit on the interstate and then coasting at 30-35 miles per hour by shutting off the engine and then starting it again, repeating the cycle of speeding up and coasting.
Green of AAA agrees with the hypermiling practice of using cruise control and overdrive gears to maintain a steady speed, which conserves fuel. "These are driving practices that consider safety first and will be beneficial to fuel economy too," he says.
Can improper tire pressure cause your car to burn more gas?
According to Department of Energy statistics, there is a 3.3 percent fuel efficiency gain if your car's tire pressure is correct. Experts agree that the condition of tires, their pressure and their size are all very important to fuel economy. Always follow the car manufacturer's specifications for tire pressure and never stray from it. You can find the correct specifications for your vehicle inside the driver's door, between the console center and the floor shifter or inside the fuel filler door.
How often should you check tire pressure? MacEachern says, "Check tire pressure with the changing seasons as it fluctuates from spring to summer to winter." Automotive expert Goss takes it a step further, and recommends checking tire pressure every week and never going over a month with out checking it.
Is it true that you should check your air filter, oil and spark plugs if you're trying to save fuel?
When it comes to saving gas, every component of a car is important to maintain and no part supercedes another. Experts agree regular tune-ups are very important for fuel efficiency.
Goss says there is a misconception that air filters on modern cars affect performance and fuel economy. That is false. The truth is that in today's cars, a computer measures the amount of air coming out of the filter and automatically adjusts the air to match the amount of fuel. In older cars built before the mid '90s, Goss says the air filter can have a significant effect on your car's performance, but not its fuel economy.
Make sure you get regular oil changes too. As far as the type, viscosity and amount of oil, Goss recommends sticking to the specifications of the manufacturer -- unless you are an oil engineer.
Goss also says if you notice a drop in your car's performance or mileage, check the spark plugs first as they are what give a spark to the fuel so it can burn and drive the engine.
products on the market that claim to improve a car's fuel efficiency. Do they work?
Don't waste time and money trying the many additives, special magnets and other products that claim to help with fuel efficiency, Goss says. "General Motors would not be on the verge of bankruptcy if a single one of these products worked," he says. "They would buy the patent for $10 billion and apply it to all their cars." MacEachern adds that gasoline molecules are not magnetic, so magnets are useless.
Does taking shorter trips really impact fuel economy?
"Plan your travel and make it a circuit," says Alan Pisarski, author of the book series "Commuting in America." When you get in your car, be sure you know exactly where you're going, get maps, get your GPS working, so that you don't waste time/ fuel looking for the place. On your way home from work, stop by the pharmacist, the grocery store and the dry cleaners. It will save you a lot of fuel in the long run, Pisarski advises. You might also try keeping a before-and-after diary of how much you drive as well as your gas mileage. The results may surprise you.
Can removing excess weight from a car help?
"How much stuff do you haul around?" asks Pisarski. Make sure you are not carrying unnecessary weight in your trunk. Remove the golf clubs, the tennis rackets, the cycle rack, the extra pair of shoes, etc. Also, remove your roof rack. Sure, it looks cool to advertise that you like to go camping, but having it will cut into your gas mileage, say Click and Clack. But don't remove your spare -- it's there for your safety and you may need it.
Does buying gas in the morning give you more for your money?
A common misconception is that buying gasoline in the morning, when it is cooler, can help you save money. The truth is that gasoline can vary its density with temperature, just like any other fluid, but the temperature of the gasoline in the ground doesn't change all that much except for a few degrees a year, Goss explains. The Environmental Protection Agency (EPA) has ruled out time of day as a factor in fuel economy.
Goss recommends that drivers avoid filling up at a gas station where a tank truck is unloading. The truck has likely traveled a long distance in the sun and contains gas that is hotter and less dense.