Air conditioning in your home does a number on your electric bill, so it must drain your gas tank too, right? Not so much. Auto testing at Consumer Reports proves that running the AC uses such a nominal amount more in gas, you may as well turn on the AC and be comfortable on a hot day. Rolling down your windows can add drag, zapping your car's efficiency; for best gas mileage, run the fan and keep your windows rolled up.
2. Filling Up When It's Cold Outside
Get your gas in the evening or early morning -- the fuel is cold, and therefore denser. The truth about this myth is that you can barely register a temperature difference, since gas is stored in cool underground tanks, so fill up when you want. There are no savings to be had by waiting until it's cool out.
3. Increasing Tire Pressure
To get the most out of your gallon of gas, you should pump up those tires, some say. While driving on underinflated tires can cost you 3.75% in fuel economy, overinflating tires can be downright dangerous, since it reduces your grip on the road and could cause an accident. Proper tire inflation is important for safety and longevity of your tires, but don't expect any significant gas savings there.
4. Pouring Additives
Where there's a need, there's a product, but that doesn't mean it actually works. Our desire for better fuel economy seems answered by fuel additives and even bolt-on devices -- but they're a complete waste of money according to the Environmental Protection Agency (EPA).
5. Changing the Air Filter
Taking care of your car is a good thing: You'll be able to drive it longer, and get the most for your money. Don't expect maintenance like changing the air filter to get you more miles out of the gas tank, though. Consumer Reports tests have shown that with today's computerized cars, clogged air filters don't actually reduce fuel economy. Take care of your car to make it last, but don't look at air filters to reduce your gas expense.
6. Keeping the Engine Running
Starting a car sucks up fuel, some say, so keep the engine idling when possible. That's bad advice: today's fuel-injected vehicles are efficient and don't waste gas during start-ups anymore. In fact, idling can cost you up to half a gallon of gas an hour, so turn off the engine if you're not going anywhere.
The Bottom Line
There are a lot of myths out there when it comes to saving gas. So what does actually help improve your fuel economy? Instead of looking at your car to improve fuel economy, try changing the way you drive. Calm driving on the highway -- not zipping between lanes, tailgating or revving the engine so you quickly get up to speed -- can improve your fuel efficiency a whopping 33%. Remove any excess weight from your car to bump fuel economy another 2%, and drive sixty miles an hour (when the speed limit allows) on the highway for another 23% improvement in fuel efficiency. In the end, best fuel economy comes from a calm and safe driver, something that's a good thing regardless of the price we pay at the pump.
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