It is a common practice to let your engine idle to warm it up, especially on cold mornings. Did you know that some people also let their engine idle all day? Many people who work in the oil field and on farms use their engines to run equipment that they need for their work. So, they leave their vehicles idling, because they think it increases the engines performance.

Whether you let your engine warm up for 10 minutes or idle it for 10 hours, you’re damaging it. Why? Because newer engines are made for motion, not to sit and idle. We have heard a lot of reasons why our customers continue with this practice, so let’s address a few of them!

But my dad always said to warm up my engine! 

Warming up your vehicle before driving is a leftover practice from a time when carburetor engines dominated the roads. Carburetors mix gasoline and air to make vaporized fuel to run an engine. However, they did not have a sensor that tweaked the amount of gasoline that is injected into the engine. So, you had to let older vehicles warm up before driving or they would stall out. But it’s been about 30 years since carbureted engines were common in vehicles. Carbureted engines were phased out in the late 1980s and early 1990s. So, unless you’re still driving your dad’s treasured pickup from 1975, you need to let go of this practice.

That does not apply to my vehicle…

While a lot of the mechanics on diesel and gasoline engines differ, this is true for both diesel and gasoline engines. Until your engine has warmed up to its optimal temperature, you should drive your vehicle gently, not let it idle. In the past, gelling diesel fuel used to be a problem, but refiners have worked to resolve this issue by creating winter blends that better withstand colder temperatures.

You are just plain wrong! 

Change is hard, but let’s examine what unnecessary idling does to your engine. Idling causes twice the wear and tear on internal parts compared to driving at regular highway speeds. This increases maintenance costs and shortens the life of the engine. Idling strips lubricating oil away from the engine’s cylinders and pistons.

Even though warm air generated by the radiator will flow into the cabin after a few minutes, idling does surprisingly little to warm the actual engine. Driving your car is the fastest way to warm the engine up to 40 degrees Fahrenheit. Once at that temperature, the fuel injection system switches back to a normal air/fuel ratio.

But, but, BUT!

Still don’t believe it? Check your owner’s manual to find out the guidelines on idling for your vehicle.