Leir Technologies: Fuel Saving Efficiency

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Toyota Estima Hybrid Minivan

Tips for Fuel Economy

Reduce the amount of gas your car uses, so that you:

Save money
Reduce pollution
Reduce dependence on foreign countries

When you use your car daily, then a small daily cost adds up to a big yearly cost.

With millions of vehicles on the road, even a few percent reduction in fuel usage will have large benefits to the environment.

This tip sheet will remind you of all the ways you can reduce fuel consumption.

Honda Insight Hybrid Car

Mechanical Factors

Tires

Perhaps the most overlooked thing is incorrect tire pressure. Many people do not check their tire pressure regularly, and all tires have slow leaks. Also, many people assume the tire shop sets the pressure correctly. A tire shop recently put air in my tires in their warm garage, and even noted the pressure on the bill, and of course the pressure was wrong as soon as the tires cooled down outside. Many tire shops are not so careful, and just put 30 pounds in tires for all cars. Remember that in the autumn you will always be adding air, and in the spring you will be often letting some out. To find the correct pressure, look for a label on the door pillar or in the glove compartment.

Do you have over-sized tires? Wider tires will increase fuel consumption.

Tread pattern is also important, so don't use snow tires in the summer. Look for "M+S" on the sidewall, indicating 'Mud and Snow'. These tires are good in snow, but they will increase fuel consumption.

All season tires are a good compromise between M+S and summer tires. They have mostly replaced the summer tires we used to use, so it can be hard to locate summer tires. You might consider having two sets of tires and extra wheels so you can easily swap on winter or summer tires.

Wheel alignment is important, but the repair shops overrate this factor. Your alignment is probably OK unless you drive over a curb fast, or hit a big chuck hole. Otherwise you can drive for 20 years without needing realignment.

Ford Escape Hybrid SUV

Engine

The grade of oil you use affects the efficiency of the engine. Lighter oils such as 5W30 are better unless you need a heavier grade. Check your car's User Manual. You might want to use different grades for summer and winter.

The grade of gasoline does not affect fuel efficiency (despite the claims of some gas station owners). Premium and regular have almost the same chemical energy content, but premium has additives to raise the octane rating. You pay more for premium, so check your car's User Manual to see if you need it. Most cars don't need it, but high compression performance engines may need it to avoid knocking or pinging.

Newer engines have ping detectors which compensate by retarding the ignition timing, so your User Manual may give you the option of using premium for better performance. You are paying a price for a minor performance gain.

In the winter, regular is preferable because cold starting is easier. Some gas companies modify the blend to suit the season, so you will see ads for 'Winter Gas' which has a lower octane rating and perhaps some methanol added.

Some gas companies add a detergent to the premium blends to help clean your injectors, but it is unfortunate if you have to pay for the unnecessarily high octane just to get the detergent additives. Maybe you would do better to occasionally buy a bottle of injector cleaner.

Many engine problems can affect efficiency, such as

dirty fuel injectors
leaky cylinder valves
worn piston rings
dirty oxygen sensor
clogged EGR valve and
dirty spark plugs.

Modern engines are reliable and will work fine for years. I say "If it ain't broke don't fix it" because a botched repair job can result in a poorly running engine.

Many mechanics will want to change the air filter as part of a tune up. However, this only helps you when you are accelerating 'wide open' and so it does not help normal driving conditions. Save money and only change it when it is really dirty.

Brakes

Check that your brakes are not dragging. The quick way to do this is to go for a drive on the highway then stop and touch the wheel nuts (you may need to remove the wheel covers). If they are warm then the brakes may be dragging. A better way to check is to jack up the car and see if you can turn each wheel by hand. Or just ask your mechanic.

Weight:

Do you drive around the city with a tool box in the trunk? The extra weight will cost you in fuel, though it is not such a handicap for highway driving.

Air Drag:

Don't drive with the windows open, use the air conditioner instead. Don't leave your roof rack on the car all the time. Don't use a wind deflector on the windows, or in front of roof rack. Don't remove the sheathing under the engine compartment.

Car body looks are deceiving. The 'wedge' style is not the best for reducing drag. Cars with a low Coefficient of Drag have smoothly rounded corners front and rear, and a small frontal area.

Driving Habits

Try to maintain a constant speed. Stop and go driving is bad for fuel efficiency. Speed obviously is a factor, and fuel consumption rises sharply at high speeds.

When you see a red light ahead, get off the gas and coast. There is no point in driving fast towards it and then braking to stop. However, the drivers behind you will be annoyed if you take this to extremes. Allow them to pass easily if they want to rush up to the light.

With some automatic transmissions, Over Drive (O/D) can be disabled by pushing a button. Don't disable it. If your kids like to get in the parked car and push buttons, check that they don't leave it disabled.

If your car has a standard gearbox, don't spend much time in low gear. Shift up as soon as you can. Volkswagen used to have a dashboard light which would come on at the optimal time to shift up.

Choice of Vehicle

Hybrid

When you buy a hybrid from Toyota or Honda you will be happy knowing that you are reducing pollution and conserving resources. Fuel is saved because when you are braking you recharge the battery, and the electrical energy is used to help you get going again. Fuel is also saved because the car can be designed with a smaller gas engine. Fuel savings are excellent for city driving, but you don't save as much on the highway. The higher purchase cost is justified if you do a lot of driving. A taxi driver claims he justified it in the first two years (from an article in a Canadian newspaper).

Sedan

In general, smaller is better. A lighter car will save fuel around town, and a car with a low Coefficient of Drag will save fuel on the highway.

4 wheel drive

People in Vermont and Colorado who have a steep driveway need to have 4 wheel drive. All the rest of us are just increasing our fuel costs needlessly. Choose front wheel drive instead.

Pickup

Contractors and farmers need to drive trucks, but there are too many people driving them for 'fun'.

SUV

Why are you reading this page? Go browse somewhere else, or turn off your PC and go soak your head.

Minivan

There are many good reasons for having a minivan but fuel efficiency can be poor. Get a 4 cylinder model and don't drive with a lead foot. Or reconsider a station wagon.

Check the Numbers

Before you get your next car, check its efficiency as tested by Natural Resources Canada or the Transport Canada Fuel Consumption Guide or the United States Department of Energy . There is an excellent unbiased site about all aspects of hybrid cars, at www.hybridcars.com

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