This is where the 1.8 DiD engine proves that the Mitsubishi ASX offers a significant advance. It is not the fastest car in its class – to 60mph we were 0.3sec off Mitsubishi’s claimed 9.7sec 0-62mph time – but that’s competitive with most 2.0-litre diesel cars in the class.
In practice, in-gear flexibility matters far more than outright pace, and the ASX doesn’t disappoint here. One of the claimed benefits of variable valve timing on diesel engines is improved low-down torque. This is most apparent in the ASX’s 50-70mph time in sixth gear, which betters some of the best engines in the class by as much as 0.9sec, including those with shorter gearing.
This makes for an engine that responds well to throttle inputs, even from low revs. It still has the non-linear power delivery that’s a characteristic of most small-capacity turbodiesels, but it’s pleasant to make rapid progress with slightly fewer downchanges than might be required in other turbodiesels.
The low-down torque also allows for easy progress in high gears at urban speeds, which will be one of the few occasions when the cabin isn’t filled with a high-pitched turbo whine and bass diesel dirge. Mitsubishi has created a usable and arguably revolutionary motor that is easily the most impressive aspect of the ASX, but refinement falls noticeably short of the latest class rivals’, even if engine noise does subside under light load.