Seeing as we live in an area that experiences less-than-ideal weather during the winter months, it can be crucial to know when to plug in your engine's block heater, and for how long you need to leave it plugged in. Even though most people who use engine block heaters drive a diesel, the extreme cold can sometimes have an effect on gasoline engines as well, and it could be beneficial to know when to plug your vehicle in. But first, let's take a look at how an engine block heater works.
As you know, most things don't especially like extremely cold temperatures, and the engine in your vehicle is no exception. When the temperature outside gets really cold, it causes the oil in your vehicle to thicken up. You know that your vehicle is dependent on oil to run properly, but did you know that if your oil is too thick it won't be able to flow like it normally does? Less flow causes more friction in your engine, and more friction causes your moving parts to wear down a lot faster than normal. With an engine block heater, you'll be able to keep the oil in your engine at an ideal temperature in order to keep it thin and flowing.
There are many different factors that can go into when you should plug your engine block heater in. A general rule of thumb is to plug it in for at least 2-3 hours, and if it's especially cold outside, possibly even longer. A lot of people will say that simply starting the vehicle and letting it idle is a good enough way to warm up the oil and the engine. While this does work, idling is extremely bad for your fuel efficiency, and even causes the engine to produce more harmful emissions. Cold engines burn more gas and burning more gas to idle means you'll have to make more trips to Petro-Canada in order to keep you tank full.
The longest you'll ever have to keep your engine block heater plugged in for is four hours. Keeping it plugged in longer than that is simply wasting your money by raising your electricity bill. Keep an eye on the temperature outside and plug your engine in for a little longer on the colder mornings before heading off to work. You can even get a block heater timer which will automatically shut off your engine block heater after a certain amount of time so you don't have to worry about remembering to unplug it.