The Facts Behind Warming Up Your Engine

Scientific studies reveal the truth: You shouldn't “warm-up” your in the winter before starting to drive. Doing so creates unnecessary pollution.

Experts ranging from the U.S. EPA to Natural Resources Canada and “Car Talk” agree - warming up your vehicle's engine before driving has virtually zero benefit for your car's engine. In some cases, pre-drive idling can help defrost your car a little, but even then, actually driving the automobile is the most efficient way to increase the engine's temperature.

Regardless, a 2009 study of 1,300 people in the U.S. found that, people believe cars and trucks should be “heated up” for 5.1 minutes when the temperature is below freezing. This myth has led to:

  • For each car, almost $10 per year wear and tear costs
  • Increased personal breathing of polluted air while sitting in idling autos
  • On a national level, 40,000 tons per day of unnecessary CO2 alone emitted into the atmosphere
  • Throughout the U.S., 3.8 million gallons in wasted gas
  • For every car or truck “warmed up”, up to $183 each year in wasted gas

The beginnings of this idea that cars and trucks need to be idled to warm up are based on a time when it was true. Before electronic starters and electronic fuel injection, cars used carburetors to blend air and fuel for the engine. If a car was driven cold, that mix could be off, causing the engine to stall. Today, the vast majority of cars have updated technology. In addition to conserving fuel at startup, electronics measure the engine temperature and make up for hot and cold conditions. Now, experts say to idle your car for 10 seconds or less before starting to drive.

If you stop idling, there will be many positive effects. Your auto will drive better and heat up faster. A car that is on the road also starts the process of filtering the tailpipe air more quickly by way of the catalytic converter. When you are stopped, the catalytic converter doesn't kick in for about twice as long, and the polluted air your car is emitting invariably gets to you because, of course, you're not going anywhere.

If you have concerns about this or want to find out whether your car or truck needs to be warmed up, reach out to the auto professionals at Christian Brothers Spring. Avoiding idling saves time and is better for your auto, better for the air quality and better for your wallet.