eli5:Why do cars consume more fuel in cold weather?


I noticed my car burns more fuel in winter. I don’t use the heater or Air Con. So all being equal why more fuel? Is it something to do with Oxygen density in cold weather? If so, please explain 🙂

In: 9

Combustion engines run off a series of controlled explosions. When it is cold, it takes more fuel (gasoline) to make an equal explosion to when it is warm.

Air fuel ratio. Colder air is denser than warmer air so more air is going into the cylinders requiring more fuel for proper ratio.

A few reasons:

-Air density, winter air averages about 10% denser than summer air, so more fuel goes in with it.

-Winters on average have stronger winds, meaning more aerodynamic drag.

-Colder parts in the powertrain makes more friction, meaning some additional loss of power efficiency.

Why don’t you use the heater? It shouldn’t affect fuel economy like ac does, and ac is more efficient than wind drag in the summer at highway speeds.

Warming up the car also uses some fuel, and you should be doing that.

in the cold weather tires loose some air. make sure you drive with the correct tire pressure. driving with lower pressures will impact fuel comsumption.