At idle the engine sounds much like you'd expect of a muscle car, with a loud and low burble. (evo.co.uk)
You also get automatic stop / start and, in combination with the dual - clutch gearbox, a coasting function that idles the engine on extended periods of trailing throttle for added fuel savings. (autoweek.com)
«How behavioral science can help tackle problem of idling engines.» (sciencedaily.com)