Although it sounds like a utilitarian throwback to find the Mercedes' 2.1-litre, four-cylinder engine in a car like this, it shouldn’t, given the capability of the ML 250.
Its 93bhp per litre isn’t uncommon by modern diesel standards, but it still takes some getting used to for those of us who remember (and it wasn’t so long ago) when 100bhp per litre was considered at the sharp end for naturally aspirated petrol cars.
But the 201bhp peak isn’t only what makes this 2.1-litre engine sufficient in the 2310kg (as tested) ML; it’s also the exceptional 369lb ft of torque, a broad spread of it, and the ability of the seven-speed auto ’box to make the most of the power and torque delivery.
It still leaves the ML 250 looking a touch malnourished compared with some of its bigger-engined rivals, but it would be churlish to suggest that an 8.8sec 0-60mph dash in a car like this is insufficient.
In-gear flexibility is decent if you hold on to the gearbox’s ratios via its steering wheel paddles; 50-70mph in seventh, for example, takes a respectable time of 11.0sec. But even with the gearbox thus selected, you can kick past holding on to a ratio if you’re determined to give the carpet a hard time. Flat out through the gears, the same 50-70mph benchmark can be achieved in a sprightly 5.8sec.