What is it?
Audi’s decision to break conventions by using a mild-hybrid diesel V6 for its middleweight sporty models is about to extend to the classy SQ5 TDI, due in showrooms in a couple of months and available for order now.
Like the S6 saloon and S7 Sportback, the sporty soft-roader has a newly developed 3.0-litre diesel V6, working with a 48V integrated starter-generator that collects power on the overrun and deploys it during acceleration, to deliver its impressive performance.
Like its siblings, the SQ5 engine’s turbocharger is fed at low crankshaft speeds by an electric compressor that feeds the turbo impeller and greatly reduces turbo lag. Working together, the starter-generator and V6 produce 342bhp at a relaxed 3850rpm (a power output slightly lower than the saloons because of different manifolding) but an identical 516lb ft of torque between 2500rpm and 3100rpm. Performance matches that of the two new Audi S saloons: the 0-62mph sprint takes a very brisk 5.1sec, and the SQ5 TDI is governed at 155mph, like every other car in its class.
The fuel consumption story is impressive: using latest WLTP rules, the SQ5 returns 34.4mpg combined, usefully undercutting the outgoing 3.0 TFSI model and soundly beating petrol-engined competitors like the Mercedes-AMG GLC 43 4Matic (around £6000 cheaper at £49,890) by a cool 10mpg. Audi will be hoping buyers respond to their model’s efficiency and long range, and not be deterred (as buyers in other markets recently have been) by the fact that it’s a diesel.