Engine Warm-Ups & Air Quality

Scientists agree: It's a waste of time and money to “warm up” your vehicle in wintry weather before starting to drive. This adds significantly to environmental pollution.

Experts ranging from the Environmental Protection Agency to the government of Canada and the late host of NPR's “Car Talk” program agree - idling in the driveway has virtually no benefit for your car. Sometimes, pre-drive idling can make your car more comfortable a bit, but even then, getting the car moving is the most efficient way to raise the engine's temperature.

Nevertheless, a 2009 scientific survey of about 1,300 people in the U.S. found that on average, people believe autos ought to be idled for about five minutes when the temperature is below freezing. That belief has meant:

  • For each vehicle, $9 each year maintenance costs
  • Increased personal breathing of polluted air while sitting in stopped vehicles
  • Nationally, 13 million tons per year of unnecessary CO2 emitted into the air
  • Nationally, $5.9 billion per year in wasted fuel
  • For each vehicle “warmed up”, up to $183 per year in wasted fuel

The foundations of the myth that automobiles need to be heated up are based on a time when it was true. Before the advent of fuel injection and electronic starters, vehicles used carburetors to mix air and fuel for the engine. If a car had not been warmed up before being driven, that mixture could be wrong, causing the engine to stall. Most cars now, though, have updated technology. In addition to saving gas at startup, electronics monitor engine temperature. Now, you should idle your engine for no longer than 10 seconds before driving.

When you make this change in your driving behavior, there will be many beneficial effects. First, your car will drive better and heat up sooner. An automobile that is moving also starts the process of cleaning its emissions faster. When you aren't driving, the catalytic converter doesn't kick in for approximately twice as long, and the polluted air your car is emitting inevitably gets to you because, of course, you're not moving.

If you have concerns about this or want to find out whether your vehicle needs to be heated up before driving, call the auto professionals at Christian Brothers Rockwall. Not idling saves time and is good for your car, good for the environment and better for your budget.