You can boost the overall fuel-efficiency of your car as much as 30%
by simple vehicle maintenance and attention to your style of driving.
Here are some tips on fuel-efficient driving that will not only reduce greenhouse gas emissions and other pollutants, but could save you hundreds of dollars a year in fuel costs.
Tips for Fuel-Efficient Driving
Avoid Aggressive Driving
“Jack-rabbit” starts and hard braking can increase fuel consumption by as much as 40%. Tests show that “jackrabbit” starts and hard braking reduces travel time by only four percent, while toxic emissions were more than five times higher. The proper way is to accelerate slowly and smoothly, then get into high gear as quickly as possible. In city driving, nearly 50% of the energy needed to power your car goes to acceleration.
Deceleration also affects fuel efficiency. Instead of breaking to stop your car, anticipate traffic flow as much as possible and coast to decelerate. In fuel-injection vehicles, removing your foot from the accelerator automatically stops the flow of fuel to the engine until the engine speed drops to idle—when it starts again to ensure your car doesn’t stall. Coasting to decelerate also saves wear and tear on your brakes.
Drive Steadily at Posted Speed Limits
Maintaining a steady speed helps your engine perform efficiently. In one study conducted in Japan, small variations in speed were shown to increase fuel consumption by as much as 20-48%. Instead of allowing small dips in speed followed by bursts of acceleration, maintain a steady speed. When traveling in hilly terrain and where traffic permits, allow your car to slow down naturally when traveling uphill and to speed up again when going downhill.
Increasing your highway cruising speed from 55mph (90km/h) to 75mph (120km/h) can raise fuel consumption as much as 20%. You can improve your gas mileage 10 – 15% by driving at 55mph rather than 65mph (104km/h). Natural Resources Canada puts the “sweet spot” for most cars, trucks, and SUVs even lower, between 30 mph (50 km/h) and 50 mph (80 km/h).
Note how quickly efficiency drops after 60 mph.
Avoid Idling Your Vehicle in Both Summer and Winter
Idling wastes fuel, gets you nowhere, and produces unnecessary greenhouse gases. If you’re going to stop for more than 30 seconds, except in traffic, turn off the engine. In winter, don’t idle a cold engine for more than 30 seconds before driving away. Older vehicles, however, may need more idling time when first started. In cold, wintery conditions, all vehicles may need more idling time to warm up and ensure the windshield is fully defogged. Be sure your vehicle is warmed enough to prevent stalling when you pull out.
Make Sure Your Tires Are Properly Inflated to Prevent Rolling Resistance
Under-Inflated Tires Can Cause Fuel Consumption to Increase by as much as 6%. Check tire pressure at least once a month, when the tires are ‘cold’ (i.e. when the vehicle has not been driven for at least three hours or for more than 2km). Start by checking tire pressures in your driveway. Note any tire that is underinflated, and then drive to the nearest gas station to add air. Check tire pressures again at the station, and inflate the low tires to the same level as the others (these will likely have higher pressure than they did in the driveway, since the tires have heated up.)
Radial tires can be under inflated yet still look normal. Always use your own tire gauge for consistent results. On average, tires lose about 1 psi per month and 1 psi for every 10 degree drop in temperature.
To determine the correct tire inflation for your car, consult the car’s operator manual or ask your tire dealer. Do not inflate your tires to the ‘maximum allowed’ pressure which is marked on the side of your tires.
According to the Energy Information Administration, tire efficiency could save approximately 800,000 barrels of oil a day.
Select the Right Gear
Change up through the gears and into top gear as soon as possible without accelerating harder than necessary. Driving in a gear lower than you need wastes fuel; so does letting the engine labour in top gear on hills and corners. Automatic transmissions will shift up more quickly and smoothly if you ease back slightly on the accelerator once the car gathers momentum.
Use Your Air Conditioner Sparingly on Older Cars
Using a vehicle’s air conditioner on a hot summer day can increase fuel consumption as much as 10% in city driving. If it’s cool enough, use the flow-through ventilation on your car instead of the air conditioner. At low speeds, opening the window will also reduce fuel consumption by reducing A/C use. At higher speeds, however, using the A/C may be more efficient than the wind resistance from open windows and sunroof.
Later model cars have more efficient air conditioning units, and the fuel saved by shutting down the A/C is not significant. In newer vehicles, roll up the windows and enjoy the A/C during hot weather.
Use the Cruise Control
On long stretches of highway driving, cruise control can save fuel by helping your car maintain a steady speed. However, this efficiency is lost on steep hills where the cruise control tries to maintain even speeds. In hilly terrain, it is best to turn off the cruise control.
Choose the Octane Fuel Which Best Suits Your Car
Premium, high-octane fuels aren’t necessarily the best choice for your car; higher price doesn’t guarantee better performance. In fact, such fuels don’t provide any greater fuel efficiency. Many cars are designed to use regular low-octane fuel. Check your owner’s manual to see what your car requires.
Service Your Vehicle Regularly, According to Manufacturer’s Instructions
A poorly tuned engine can use up to 50% more fuel and produces up to 50% more emissions than one that is running properly.
What About Hybrids?
Most of the tips above apply to hybrid and gas-powered vehicles alike. To maximize fuel use in a hybrid vehicle:
Use Your Brakes
Since braking in a hybrid vehicle recharges your battery, you’ll want to make the most of this feature. Give yourself plenty of time to brake, applying steady, even pressure that allows you to coast to a full stop. Avoid hard braking.
Maintain a Low and Steady Speed
In a hybrid, efficiency will start to decline at speeds over 55 mph.
Avoid Accelerating in Bursts
Accelerating quickly will cause both your gas and electric engines to work at the same time. Keep your car in EV mode as much as possible by accelerating gently. Watch the dashboard fuel-economy display present in most hybrid vehicles. This will help you see what type of driving habits you need to adopt to get the most from your vehicle.
Avoid Putting Your Car in Neutral When Idling
Placing your car in neutral when stationery prevents electrical recharging; furthermore, it discharges the battery. Instead, let your idle-stop system do the work. These systems help hybrid cars save gas by automatically shutting down the engine when the car has stopped.
Keep Your Trunk Empty
A full trunk adds weight to your vehicle that’s often unnecessary. Be sure to clear your trunk of items as soon as you’re finished using them. Additionally, remove unused roof racks, car top carriers, and other attachments that may cause drag and prevent your vehicle from operating optimally.
Reduce Additional Energy Consumption
Where possible, minimize use of air conditioning systems, lights, and wipers, all of which increase energy consumption when used constantly. When using climate control, placing your system on “recirculate mode” will help save energy.