Should You Warm Up Your Car Before Driving?

Cars with electronic fuel injection do not need to be warmed up before lightly driving off. This is because fuel injected engines can compensate for temperature changes. Cold engines run rich to compensate for poor fuel atomization. This means extra fuel is injected into the combustion chamber.

Now fuel is a solvent, so when extra fuel gets on the cylinder walls, it washes away the gasoline from the cylinders and pistons. Less oil on the cylinder walls means less protection, and because the oil is cold it makes it harder for it to be replaced. This means the longer you spend with your engine cold, the more wear you’ll have. Idling the engine doesn’t put much heat into it, so the car remains cold for a long duration.

If it’s cold outside, you can wait 15-30 seconds to ensure that oil is flowing, but you don’t need to wait for the engine to be warm. It will heat up faster by driving the car lightly. By heating it up faster, the oil gets to operating temperature more quickly, and this is what you want to prevent wear. If it’s really cold outside, the time it takes to scrape off the windows so you can see will be plenty of time for oil to start circulating, so you can get in and go once you can see out the windshield.