Tips, Tricks & Trends

Do You Really Need to Warm up Your Car?

Believe it or not, the question “do I need to warm my car up?” is something that us car guys get asked every once in a while. While it is a simple “yes or no” answer, there are some caveats to the final answer. So let’s finally get an answer to the question: Do you really need to warm up your car after a cold start?

Get it circulating

The engine ignition start/stop button of a Volkswagen XL1 plug-in diesel-electric hybrid automobile
The start/stop ignition button for a Volkswagen XL1 | Adam Berry/Getty Images

A lot of the misconceptions behind this question is derived from the use of carbureted engines. Without the fancy computer systems that we have in our cars now – which can control the air/fuel mixture in the engine and do the calculations to compensate for almost any driving situation – those old carbureted engines didn’t have such a luxury.

As such, they needed to sit and idle for about five minutes before driving in order to get the oil up to the proper temperature and the carburetor working correctly. The carburetor was a mechanical unit that mixed the air and fuel, but they didn’t have sensors to adjust for colder temperatures. For this, they had a mechanical “choke” that would restrict the air/fuel mixture and make the engine run “richer” when it was cold.

Basically, as the engine warms up, the oil becomes more viscous and is able to coat everything properly and the gasoline atomizes into the cylinder correctly. However, if you don’t let a carbureted engine warm-up, then the oil won’t coat things successfully and the liquid gasoline can wash away the lubricating oil, which can do damage in the long run.

On newer, fuel-injected cars, you really don’t need to wait that long and can start driving but don’t get carried away.

What’s the proper way to let it warm up?

According to Popular Mechanics, if you live in a snowy area – especially in sub-zero temperatures – you should start your car up and clean off the snow like usual. A good general rule of thumb is to wait until your windows are defrosted and you’re able to drive safely, that should be enough time to get all the oil moving around in the engine.

After that, feel free to drive the car, but don’t just rip on it right away, driving it gently is key. It usually takes about 5 to 15 minutes for the car to warm up when driven gently, so just take it nice and easy and the car will eventually warm up on its own.

Do you need an engine block heater?

An engine block heater is an electrical heating element — which has a three-pronged connection – that is connected to your engine block. As you can guess, by plugging it into a socket, it warms up the engine quicker.

You may have seen an engine block heater as an accessory when purchasing your car or truck. If you live in an area that typically doesn’t see sub-zero temperatures, then you could do without one. However, if you live in an extremely cold area and want to get the engine running optimally sooner, then an engine block heater can work in your favor.

To sum things up

Long-answer short, unless your car is carbureted, you don’t really need to let your car sit and warm up while idling, especially if you live in warmer climates. Just start the car, clean off the snow (if needed), then gradually drive your car 30 mph or less, if possible. It’s a pretty simple answer to an age-old question, but at least now you know.