22 MPG combined isn’t going to win any awards, but that’s not the point of the 2023 Mercedes-Benz AMG C43 4matic Convertible. This car isn’t about squeezing every last mile from a gallon; it’s about open-air thrills, a potent engine note, and the cachet of the AMG badge. The buyer looking at this C43 convertible prioritizes performance and the experience of driving a finely engineered machine far above saving money at the pump.

City and highway performance

The 2023 AMG C43 Convertible achieves an EPA-estimated 18 MPG in the city and 28 MPG on the highway. The city figure reflects the reality of stop-and-go traffic where the 3.0L turbocharged six-cylinder engine operates well outside its optimal efficiency range. Frequent acceleration and idling take their toll. On the open road, however, the C43 fares better.

At steady highway speeds, the nine-speed automatic transmission can settle into higher gears, allowing the engine to cruise comfortably and more efficiently. The relatively high highway MPG is a welcome relief and the engineering allows some fuel efficiency even in a potent sports car.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2023 Mercedes-Benz AMG C43 4matic Convertible at $2,650. This figure is based on driving 15,000 miles per year and using national average fuel prices. Keep in mind that premium fuel is recommended (if not required) for optimal performance in this AMG model, so you’ll spend more per gallon than the average driver. Your actual fuel costs will vary depending on your driving habits, local fuel prices, and the number of miles you actually drive each year. However, $2,650 is what the EPA estimates as the cost to fuel this car.

Real-world expectations

While the EPA numbers provide a benchmark, real-world fuel economy often deviates. Expect to see figures at or below the EPA estimates, especially under enthusiastic driving conditions. The AMG C43 Convertible begs to be driven hard, and that will inevitably impact fuel consumption. Short trips, frequent acceleration, and aggressive driving styles can easily push the MPG below the official estimates. Conversely, drivers who prioritize smooth acceleration and consistent speeds might see slightly better results, inching closer to that 28 MPG highway figure. Anyone buying an AMG convertible isn’t likely hypermiling.

How it compares

Compared to its rivals, the AMG C43 Convertible’s fuel economy lands somewhere in the middle. The BMW M440i xDrive Convertible, for example, achieves a slightly better 25 MPG combined. And the Audi S5 Cabriolet is rated for 24 MPG combined. Conversely, the high-performance Porsche 911 Cabriolet models are often rated lower. The differences in MPG, while present, are unlikely to be an important factor for someone in this market segment. Performance, style, and brand prestige tend to outweigh minor variations in fuel efficiency. But you can compare AMG MPG across all years.

Tips to maximize efficiency

Minimize aggressive acceleration: The rapid bursts of power offered by the turbocharged engine are tempting, but they significantly impact fuel consumption. Smooth, gradual acceleration will help keep fuel consumption in check.

Use cruise control: On the highway, engaging cruise control helps maintain a consistent speed, reducing unnecessary fluctuations in throttle input that waste fuel. This is especially useful during longer drives on relatively flat terrain.

Keep the tires properly inflated: Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel. Regularly check and maintain the correct tire pressure as indicated on the doorjamb sticker.

Reduce idling time: Prolonged idling wastes fuel and contributes to lower city MPG. If you’re stopped for more than a minute, consider turning off the engine. Then consider the all Mercedes Benz fuel economy data.

Service the car regularly: A well-maintained engine runs more efficiently. Follow the manufacturer’s recommended maintenance schedule, including oil changes and air filter replacements, to ensure optimal performance and fuel economy.