The 2.1 L engine in the Mercedes-Benz E Class is at the top end of what this displacement produces — serious injection pressure, sophisticated turbocharger management, and a factory calibration that leaves room on the table by design. These engines are well-engineered enough that a careful, dyno-developed map extracts meaningful gains without asking anything the hardware isn't already built to handle.
Our dyno-developed map for the Mercedes-Benz E Class adds an average of 26 kW (22%) at the wheels and 125 Nm (25%) of engine torque. At this level the car genuinely changes character — overtaking on single-lane highways stops being a commitment, and the mid-range pull from around 1,500 to 3,000 rpm is transformed. You notice it most on the highway on-ramp and in the first third of an overtake.
In practical terms, that works out to around 5 fewer tanks of diesel over 40,000 km. At a typical 15,000 km annual mileage, most Mercedes-Benz E Class owners save roughly 129 L and $155 per year at the pump — purely from improved combustion efficiency at part-throttle, where diesels spend most of their time.
This Mercedes-Benz E Class variant ran from 2013–2014. The factory calibration changed very little across that production window; we have the original file for each year and always confirm which one matches the car in front of us before we start.
Mercedes-Benz OM651
The 2.1 L OM651 is the four-cylinder backbone of mid-2010s Mercedes diesels. Single- and bi-turbo variants both tune well, with notable improvement in mid-range pull on the bi-turbo cars.