- Buying premium gas when your car requires only regular will not make a noticeable difference in your fuel efficiency.
- Dirty air filters often get blamed for reducing mileage, but Consumer Reports and FuelEconomy.gov say the impact is really minimal in newer cars (although a dirty air filter may cause more sluggish acceleration).
- Another debate: whether it’s better to cruise the highway with the air conditioner on and windows closed, or to keep the windows open and the AC off. There is no significant difference in fuel efficiency, according to tests.
- Another hyped tip is to buy fuel first thing in the morning. The idea is that when temperatures are cooler, the gasoline coming from the pump is denser, so you’ll get more for your money. But since the actual temperature of gas coming from the nozzle doesn’t change during the day, you’ll likely get no savings with an early fill-up.
Sid Kirchheimer is the author of Scam-Proof Your Life (AARP Books/Sterling).