Want to save on gas? Dumb question. But, according to Investopedia, these five gas-saving tips are about as dumb.
1. Air-flow gadgets: Believed to increase an engine's airflow which will improve fuel efficiency.
In fact: Consumer Reports test showed no noticeable reduction in fuel usage despite claims of up to 50 percent. The cost of such airflow parts could be as much as $90.
2. Fuel additives: Believed that gas mileage can be improved by formulated chemicals that increase efficiency.
In fact: the Environmental Protection Agency has determined only that the product does not increase a vehicle's harmful emissions. If there were an additive that made fuel burn more efficiently, oil companies would be racing to market their new gas to gain a bigger market share.
3. Premium gas: The more expensive gas increases performance and better gas mileage.
In fact: It is true if you drive a premium vehicle that requires high-octane gas, but if you are in the majority, your car's engine is designed to run on the octane levels present in regular unleaded gas. Increasing the octane can actually cause the engine to be less efficient as the car's combustion timing is altered and efficienty is lost.
4. Overinflated tires: Rounder tires roll more easily, creating less work for the engine.
In fact: It's true to a point. However, overinflated tires wear out quickly and irregularly, creating a need for early replacements at a cost of about $50 to $100 tire. What's worse, decreased contact with the road, because of overinflated tires, increases stopping distances and limits handling capabilities. According to Edmunds.com's testing, fuel savings with overinflated tires and regular pressure tires are small.
5. Windows down instead of air conditioning: Operating the AC uses fuel, so it's more efficient to cool off by driving with the windows down.
In fact: While it's true that some fuel is used to operate the air-conditioning compressor, as much or more fuel is lost when the windows are down. It can increase the drag on the car. It's best to use the recirculation setting to force the AC to cool the hot air from outside.