GREENTIPS - Idling Gets You Nowhere

Idling Gets You Nowhere
January 2007

Would you drive a car that gets zero miles to the gallon? Of course not. Yet that is your mileage whenever your engine idles. Idling wastes money and fuel, contributes to air pollution, and generates carbon dioxide emissions that cause global warming. Some states even have laws limiting the amount of time cars can idle (see the related links).

Unfortunately, many people believe that idling is necessary or even beneficial—a false perception that has carried over from the 1970s and 1980s, when engines needed time to warm up (especially in colder temperatures). Fuel-injection vehicles, which have been the norm since the mid-1980s, can be restarted frequently without engine damage and need no more than 30 seconds to warm up even on winter days.

In fact, idling longer than that could actually damage your engine in the long term. Because an idling engine is not operating at its peak temperature‚ the fuel does not completely combust, leaving residues in the engine that can contaminate engine oil and make spark plugs dirty. Excessive idling also allows water to condense in the vehicle’s exhaust, contributing to corrosion of the exhaust system.

No matter what time of year, minimize your idling with the following tips:

* When first starting your car, idle for no more than 30 seconds.

* Except when sitting in traffic, turn your engine off if you must wait in your car for more than 30 seconds. You can still operate the radio and windows without the engine running.

* When the time comes to buy a new car, consider a hybrid. Hybrid gasoline-electric vehicles switch off the engine and use battery power for accessories when the car is not moving, effectively eliminating idling. Visit the UCS Hybrid Center website (see the related links) for more information on these fuel-efficient, low-emission vehicles.

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