Once upon a time, it was considered good practice to warm up your engine by letting it idle for a little while before setting off. These days, however, people tend to just jump in the car and go. Is that a function of everybody being impatient in the modern world, or did engines change for the better? Have you been wearing down your engine, one of the most expensive parts in the car, without realizing it?
Good news: Your impatience, for once, probably won’t come back to bite you. Engine technology actually has advanced a lot, so that even though they technically do need a little time to get ready after turning on, that time is down to around 20 or 30 seconds. In other words, just putting your seat belt on and getting comfortable is probably sufficient. That said, in extreme cold temperatures, you actually should idle the engine a little longer before heading out.
Why engines need to idle at all
An internal combustion engine has lots of moving parts. Those parts need to be properly lubricated with oil, or else they’re going to scrape against each other and cause all kinds of wear and tear. That oil, however, drains down to the bottom of the engine when not in use, so it has to be pumped back into place after ignition. Older cars took more time to do this, but modern tech has gotten this down to half a minute or less. That said, the oil takes a little longer to get moving in sub-zero temperatures, so in those situations, you’ll still want to idle for about a minute.
What about the actual engine temperature, the literal “warming up” part of the process? Engines require a specific mixture of fuel and air to, you know, combust internally. Oil pressure drops in cold weather, which in older engines with carburetors meant that the mixture wasn’t optimal until the engine temp came back up. Hence, idling for a few minutes. However, carburetors are basically a thing of the past, as nearly all modern cars use fuel injection instead. This system always provides the right mixture and pressure, regardless of temperature, which eliminates this issue.
Since batteries actually work better in low temps anyway, if you’re driving electric or hybrid, you don’t have to worry about any idle time at all. You literally can just jump in and go. Still put your seat belt on, though!
