The BMW M340i xDrive’s LCI introduced in 2022 brought mild exterior design updates (including an optional carbon fiber roof) and the iDrive 8 infotainment system. There was also one substantial change underneath the hood where the B58 calls home. No, it didn’t get a more potent engine as the turbocharged inline-six continues to make 382 horsepower and 500 Newton-meters (369 pound-feet) of torque from a 3.0-liter displacement.

We’re talking about a mild-hybrid setup with a 48V starter-generator assisting the combustion engine and providing a temporary boost of 11 hp. Aside from the extra oomph, it also helps improve the performance sedan’s efficiency. As shown in a fuel consumption test, it enables engine-off coasting to save precious gasoline.

Factoring in the usual start/stop functionality, this M340i spent nearly half of the test with its engine shut off. The run was conducted with the M Performance 3 Series in the Eco Pro driving mode and out of a total of 53 minutes and 25 seconds, the engine was off for an impressive 25 minutes and 20 seconds, or about 47% of the time. The sports sedan covered 21.8 kilometers (13.6 miles) at an average speed of 24 km/h (15 mph).

At the end of the run, the trip computer showed an average fuel consumption of 8 liters / 100 km (29.4 mpg US or 35.3 mpg UK). Doing the math after refueling showed the real fuel consumption was 2% higher. It’s important to note the M340i was running on winter tires and the test was conducted at -2 degrees Celsius (28.4 Fahrenheit) in a crowded city, so far from ideal conditions.

Of course, the M340i is no Prius, even with its newly gained mild-hybrid powertrain. Then again, Toyota’s eco-hero is not a performance sedan, nor is it a luxury vehicle. For a thriftier M Performance 3 Series, there’s always the M340d with its frugal inline-six diesel. Both M Lite models are available in a more practical Touring body style as well, proving BMW continues to cater to a wide audience.

Source: 1001cars / YouTube