Engineering-Adam: 10 Ways To Make Your Car More Fuel Efficient

With gas prices soaring world wide, I figured it was time to share a bit of the knowledge of fuel efficiency that I’ve gained in the last couple of years at school. I hope you find something here that helps you save a bit of money.

10. Pump Up Your Tires
Maintaining the correct air pressure in your tires can increase your gas mileage greatly. If your tires are 4 psi under the target pressure, your efficiency can drop by 3%. It will drop even more if you have a wider than normal tire. Your tires also lose over 1 psi per month depending on the age and condition of the tire, so checking the pressure regularly is a necessity.

9. Don’t Idle
Idling your car happens, if you are at a traffic light or behind someone turning then you’re going to have to idle. But if you know you are going to idle for more than 30 seconds, it is better to shut off your car and restart it. Modern cars are very efficient at starting, and it makes sense to shut off your engine if you aren’t going to be using it. Also, on cold mornings it is better for your gas mileage and engine to only idle for 20-30 seconds before driving easy until temperature is reached. The 20 or so seconds allows oil pressure to build. On older cars it was necessary to idle till temperature was reached, but with modern oils and fuel systems, this is no longer the case.

8. Coast
If you’re going down a long hill, it is sometimes possible to switch to neutral. This will work for you two ways, your car won’t be propelling itself, and you won’t be tempted to push the gas because you’ll be focusing on traffic around you.

7. Use The Right Oil
Using the manufacturer’s recommended oil can improve your fuel efficiency by up to 5%. Normally a synthetic oil is recommended, but if not it’s best to go with the equivalent synthetic. Synthetic oils have lower viscosity and better lubrication properties than natural oils, your car will run much better with a synthetic under the hood.

6. Keep your gas tank between 1/4 and 3/4 full
Keeping your gas tank above 1/4 full means your fuel pump won’t have to work too hard to get the fuel from the tank to your rails. So you’ll be saving on power through the alternator. In addition, not filling your car serves two purposes: Firstly, you aren’t lugging a whole lot of weight around, and secondly you don’t risk over filling your tank and losing a lot of gas to vapor.

5. Change Your Air Filter
Changing your air filter makes your car more economical, if you drive on dusty roads or around sand you should change the filter more than the manufacturer’s recommendations.

4. Use Cruise Control
Using cruise control will reduce your fuel consumption and increase your gas mileage.

You don’t have to fill the tank at the gas pump

Make sure you use your cruise control

If you are on the highway and don’t have to worry about traffic, it is much easier on your car to go 3 km/hr above and below your set point than you trying to get the speed right. Especially if you are on an undulating road where your speed might vary quite a bit.

3. Get Your Engine Tuned
Engine tuning isn’t what it used to be, since fuel injection and direct injection have come around there isn’t that much the mechanic can do to improve your fuel efficiency. They can however clean or change spark plugs, replace O2 sensors, change air filters, fuel filters, and oil. All of these things can improve your gas mileage significantly if you have been having issues in any of these areas.

2. Keep Your Speed Below 100 km/h (60 mph)
Keeping to the speed limit on the highway or slightly below reduces the amount of aerodynamic drag on your car. Rolling resistance is linear with speed, so it is a factor at lower speeds where drag isn’t.

But aerodynamic drag is a proportional to the square of speed, this means if you are going 120 km/h vs. 100 km/h you can use 10-15% more fuel than if you go a little slower. This can be a major source of fuel efficiency problems.

1. Avoid Rush Hour
It’s a simple one for the last point, avoid stop and go rush hour traffic. This traffic is a nightmare for your gas mileage, and can cause you to burn a lot more than you need to. If it’s possible it’s best to go before the rush hour, this has the added benefit that you will miss any rush hour accidents that might happen, and you’ll save money while you’re at it.

I hope these tips keep your wallet full, and your car happy.