Tuesday, April 18, 2006

Fuel Efficiency - Maximizing Your Miles Per Gallon

Here's yet another article chock full of gas saving tips. This one is from Forbes.

Vehicle Maintenance:
  1. Keep tires properly inflated. One-psi drop in pressure in all four tires can lower gas mileage by 0.4%.
  2. Follow the maintenance schedule in your owner's manual. Change oil, engine coolant, filters and spark plugs at recommended intervals. Keeping the engine tuned can save about 5% on gas. A dirty air filter can reduce gas mileage by as much as 10%.
  3. Use the recommended grade of oil. Heavy oil can reduce mileage by 1 to 2%.
  4. Use the right grade of gasoline for your vehicle. Check your owner's manual.
  5. Buy gas based on price. It's a commodity product, and one brand is as good as another. The extra additives in more expensive fuel won't necessarily make a difference in your car's performance.

Driving Habits:

  1. Drive at off-peak hours to avoid stop-and-go traffic. Try to change your commuting schedule and get to work a bit earlier or leave a bit later.
  2. Combine shorter trips.
  3. Obey the speed limit. According to the U.S. Dept. of Energy, every 5 mph you drive above 60 mph is the equivalent of adding ten cents per gallon.
  4. Use cruise control on the open highway.
  5. Use a high gear or overdrive when driving at highway speeds. Don't rev the engine in third or fourth gear.
  6. At low speeds, avoid chugging around in second gear.
  7. Resist the urge to drive aggressively (i.e., jack rabbit starts and sudden stops).
  8. Shut the engine off when you have to wait for even a short period of time. Idling your engine wastes gas. It is not more efficient to the let the engine run for several minutes.
  9. Avoid the long waits associated with left turns. Try to make right turns only.
  10. Remove the roof rack when not in use. A loaded roof rack reduces fuel economy by 5%. So, try to put as much stuff as possible in your car.
  11. Avoid using your air conditioner. It can increase gas consumption by 10-20%. Roll down your windows instead.
All in all, very good advice. But I've heard a couple of conflicting opinions on the use of air conditioning. If you're in stop-and-go traffic, you should definitely roll down your windows. But if you're driving at highway speed, it's probably more fuel efficent to use your air conditioner. The aerodynamic drag from the open windows will actually reduce your fuel economy.

For additional gas saving tips, check out the recent posts by Mapgirl and Free Money Finance and the U.S. Dept. of Energy's fuel economy website.

1 comment:

mapgirl said...

The only other thing is advice about when to idle. If your car is already warmed up and you're going to wait more than 30-60 seconds, shut your engine off. If your engine isn't warm already, leave it idling. But if you're waiting more than 5 minutes, turn it off.

Some people say that with modern engines the sensors adjust to the temperature of the car, which is why you don't have to 'warm up' a car on cold days the way you used to. I'm not so sure about this. I still warm up for about 30 seconds before I put the car in gear.