This Lifehacker Article that claims that idling your car is bad.

For those readers in chillier climates it’s a common to see people trudging out to their cars to warm them up early in the morning. It turns out all that idling isn’t just ineffective but a waste of money too.

The common belief is that you have to start a car ahead of time in cold weather or else the engine won’t be warm enough and you could damage it. It turns out that engines only require around a half minute of idle time to warm up; excessive idling decreases the life of your engine and unnecessarily kludges things up.

If you really want a good laugh at the expense of the author read the comments below the article. For example…

It’s not just your engine that needs a warm up. You want the fluids circulating freely through the automatic transmission and through the power steering system before driving off. They don’t need to be at operating temperature, but a couple of minutes to let the fluids flow and move about can save wear and tear.

The article is easily defeated by simple common sense.

Yes. The article was written with an obvious “green” bias.