For this generation of 335i, BMW earned EPA fuel economy ratings of 23 mpg city and 33 mpg highway. In my mix of city and freeway driving, the car turned in a very respectable 28 mpg.
Some of that very good fuel economy is due to the eight-speed automatic transmission, a no-cost option over the six-speed manual. Also contributing to higher efficiency is an idle-stop system, which shuts down the engine at stoplights. In the automatic, this system restarted the engine as soon as I lifted my foot from the brake, as opposed to the manual version, which kicked in the engine when I took my foot off the clutch.
I did not find this system terribly intrusive, as long as I was not looking to beat the car next to me off the line. However, with the engine cold it was a failure, as the car was prone to stalling right after a restart. If drivers find the idle-stop feature too intrusive, it can be defeated with the push of a button.
Also common to new BMWs are the Sport and Comfort buttons on the console, which took the car through three different modes: Sport, Comfort, and Eco Pro. These modes change the throttle mapping, while the eight-speed automatic also offers a Sport mode. In addition, pushing the traction control button engages BMW’s Dynamic Traction Control.
Due to the lack of a dynamic suspension, this car was missing Sport Plus and Comfort Plus modes, which I’ve seen in other BMW models. Given the basic suspension tuning of the Modern line of 335i, the Sport settings seemed pointless, the aggressive action of the engine defeated by sloppy cornering. Eco Pro, however, helped the car achieve its high-20s average fuel economy by reducing power loads in the climate control and other vehicle systems.