The last decade or so has seen tremendous strides in terms of fuel efficiency in cars, most likely due to a combination of increasing advocacy for sustainable living and rising gas prices. In fact, it isn’t uncommon to find gas-only cars today that get as many as 40 miles to the gallon, with hybrid cars getting even better mileage. Here are some features you’ll find in cars today that are making them more fuel efficient than ever.

Gasoline direct injection

Gasoline direct injection, or GDI, is a highly efficient technique for delivering fuel to a car’s engine. It’s one of the many tweaks that automakers have been making to the car’s internal combustion engine in order to eliminate inefficiencies and to burn fuel more evenly and thoroughly. While in past years GDI was a technology that posed too many technical hurdles to make it a viable option for the mainstream auto market, rising demand for fuel efficient cars has caused most car manufacturers to work around these hurdles to make GDI a standard feature in many vehicles.


Alternatively, some vehicles turn away from gasoline completely in favor of a more fuel efficient option: diesel. Today’s vehicles that run on diesel, such as the Volkswagen Jetta TDI SE, can get up to 46 miles to the gallon—without the noise and stink that used to accompany diesel engines.

Variable displacement

Variable displacement refers to an engine’s ability to essentially change the number of cylinders it runs on. An engine does this by deactivating certain valves within the engine, restricting fuel flow to the engine’s inactive cylinders. This means that you can enjoy the benefits of a V-8 engine without using all 8 cylinders at those times when it’s unnecessary.

Lighter weight

The 1990s and early 2000s saw a trend where automakers were using advances in engine technology to build heavier and more powerful cars. Trucks and SUVs were the vehicles of choice for many Americans, and this made for a high demand for heavy-duty cars that automakers responded to. The steady increase in average car weight that ensued during this time period plateaued, however, at around 2005. Since then, there has been increased demand for lighter-weight cars, and making automakers more focused on building more powerful and fuel efficient cars without adding weight.

Hybrid engines

No list of fuel-efficient features in cars would be complete, of course, without mention of the hybrid engine. A hybrid car has a traditional internal combustion engine and fuel tank, as well as an electric motor and battery pack. These cars still burn gasoline to function, but their electric components, meanwhile, collect and reuse energy that normally goes to waste in standard cars.