The Pros & Cons Of 3 Cylinder Engines

There are numerous automotive engine configurations, from the 4-cylinder variety all the way up to 16-cylinder engines, which are extremely cool but have only been used in a few production cars. While it might seem like more cylinders is always better, many auto manufacturers have been getting impressive performance out of smaller turbocharged powerplants. Take, for instance, the Dodge Hurricane engine — the standard version produces up to 420 horsepower, which eclipses both the 5.7-liter and 6.4-liter Hemi V8s.

So, if a more compact 4-cylinder can offer drivers an impressive power output, what about a 3-cylinder engine? Well, first off, 3-cylinders under the hood isn’t a new idea, and they have been available in various economy vehicles in Japan for some time. But these small engines are finally making it Stateside, with select Buick, Chevrolet, and Nissan models offering 3-cylinder motors.

As you may expect, 3-cylinder engines are more efficient than their larger brethren and sip fuel rather than guzzle it, which is a definite plus. However, they do tend to generate more vibration during operation, and they aren’t suited for quick acceleration at higher speeds. Let’s examine this compact engine configuration further, weighing the positives and negatives to help you determine if it’s a good fit for your next vehicle.

The obvious reason that 3-cylinder engines are more conservative with fuel than a 4-banger is that there is one less cylinder creating combustion. However, that’s not the only reason for the enhanced efficiency. Fewer internal components results in a smaller engine footprint. And, more importantly, this results in a reduction of weight, which can have a significant impact on fuel economy. However, it’s important to note that some assert that miles per gallon isn’t actually a good way to measure fuel economy and point to gallons used per 100 miles as a better metric. Regardless, according to the U.S. Dept. of Energy, 100 extra pounds can lower miles per gallon as much as 2%, with smaller cars being more effected than larger vehicles. So, especially in a compact vehicle, the lighter engine contributes to better gas mileage.

For example, the 2026 Chevy Trax — a subcompact SUV that sports a turbocharged inline 3-cylinder engine — tips the scales at just over 3,000 pounds and achieves a combined EPA estimated fuel economy of 30 mpg. The 2025 Honda HR-V EX-L, on the other hand, features an inline 4-cylinder engine under the hood, is more than 260 pounds heavier, and gets a combined 27 miles per gallon.

If you’re looking for a car that feels buttery smooth while the engine idles, you’ll want to avoid a 3-cylinder. These smaller engines run in a way that feels noticeably less refined than other configurations, due to the odd number of cylinders. The firing order is such that there is one cylinder firing during a rotation and then two going off in the next. This creates the perception that things under the hood aren’t healthy, but it’s just a quirk of the design. This is in comparison to how a 4-cylinder runs, where each rotation features two cylinders firing in an even operation.

While some turbocharged 3-cylinders like the Chevy Trax can manage a decent 0-60 time in 8.8 seconds, things are different on the highway. These smaller engines don’t have gusto at higher RPMs and are lackluster in terms of power on the freeway. Also, it isn’t just idling where these compact engines sound rough, it’s also during acceleration. So, not only will you potentially struggle to pass another motorist on the highway, but your car won’t sound particularly good doing it, either.

When you drop an engines cylinder count to three, there aren’t as many moving parts generating friction. Any time you have metal surfaces contacting each other, there will be something called mechanical friction loss. Essentially, as metal components rub against one another, heat is generated. This heat represents the energy used and lost as engine components work against each other’s surface resistance. This is present even when fluids and lubrication are at optimal levels.

However, with one less cylinder, these compact engines not only use less fuel because of the reduced friction, but it could also translate into lower maintenance costs. Essentially, an engine with fewer moving parts has less potential points of failure. Many drivers fail to consider the price of their vehicles beyond the initial purchase. Just look at these car brands that cost the most to maintain and repair over 10 years according to Consumer Reports for an idea of how bad things can get. Depending on the 3-cylinder, it could offer a less complex design than a 4-cylinder, potentially saving you money.