General Motors Europe has introduced its first Euro 4 emission-compliant diesel car model, the Opel/Vauxhall Astra 1.7 CDTi, claiming better performance, greater running smoothness and “greatly reduced” exhaust gas pollutants. The 1686cc 16v 80PS four-cylinder EcoTec turbo diesel, with two overhead camshafts and common rail direct fuel injection, produces a maximum torque of 170Nm and a top speed of 108mph in saloon and hatchback models.