The Mercedes ML 350 CDI 258hp (W166 - 2011 ->) produces 258bhp and 620Nm in standard form. Our Stage 1 ECU tuning file raises output to 290bhp and 690Nm, a gain of 32bhp and 70Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.