Title: Idling- Did you know..?




  • Idling gets you nowhere - and it can be costly. Excessive idling wastes an enormous amount of fuel and money and generates needless greenhouse gas emissions.

  • In winter conditions, emissions from idling vehicle are more than double the normal level immediately after a cold start.

  • Warming up the engine means more than the engine. The tires, transmission, wheel bearings and other moving parts also need to warm for the vehicle to perform well. Most of these parts do not warm until the vehicle is driven.

  • Once a vehicle is running, the best way to warm it up is drive it. With computer controlled, fuel-injected engines, you need no more than 30 seconds of idling on winter days before driving away.

  • The catalytic converter - the device that cleans pollutants from the vehicle exhaust - does not function at its peak until it reached between 750 and 1500 degrees Fahrenheit. The best way to warm the converter is to drive the vehicle.

  • Idling emits more pollution if the catalytic converter is not working properly. Ask your technician to check the system the next time your car is being serviced.

  • Driving a vehicle cuts warm-up times in half. This reduces fuel consumption and greenhouse gas emissions.

  • Ten seconds of idling can use more fuel than turning off the engine and restarting it. If you are stopped for more than 10 seconds - except in traffic - turn off your engine.

  • Every 10 minutes of idling costs you at least 2/10 (0.2) of a gallon of gas - and up about 7/10 (0.7) of a gallon for an 8-cylinder engine. Keep in mind that every gallon of gas you use you produce about 19 pounds of carbon dioxide.

  • Excessive idling can be hard on your engine. Because an engine is not working at its peak operating temperature, fuel does not undergo complete combustion. This leaves fuel residue that contaminates engine oil and makes spark plugs dirty.

  • Restarting a car many times has little impact on engine components such as the battery and the starter motor. The wear on parts that restarting the engine causes adds about $10 a year to the cost of driving - money that you'll likely recover several times over in fuel savings.

  • Its important to drive away as soon as possible after a cold start. But avoid high speeds and rapid acceleration for the first 3-5 miles. This lets the whole vehicle reach peak operating temperature as quickly as possible without paying a fuel penalty.

  • If your vehicle has a diesel engine, idling actually lowers the coolant temperature faster than shutting off the engine. In other words, switching off the engine keeps the engine warm longer

  • A poorly tuned engine uses up to 15 percent more energy when idling than a well-tuned vehicle. Keeping your vehicle in good condition is a key to fuel efficiency and reduced greenhouse gas emissions.

  • Idling your vehicle with the air conditioner on (to keep the interior cool) can increase emissions by 13 percent.

  • Warming up a vehicle is the most common reason given for idling - in both winter and summer! Many drivers also say that they often idle while sitting in the drive-through lane of a fast-food restaurant or while waiting for someone.

Thank you to the Office of Energy Efficiency of Natural

Resources Canada for this information.


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Air Quality Mangement Division