General Motors Europe has announced the development of a new diesel particulate filter (DPF) system for its Vauxhall and Opel diesel cars.

Using a platinum catalyst, which is to be fitted to the Vectra and Signum lines with new 1.9 litre CDTi Ecotec engines, the cars will be made fully Euro 4 (2005) compliant.

The system combines a close-coupled precatalyst, an oxidation catalyst (under the floor), and a monolithic, silicon carbide (SiC) diesel particulate filter catalyzed with a precious metal catalyst.

The manufacturer claims the emission reduction controls are such that the car will be eligible for emissions-related tax incentives in countries that offer them.

GME follows Mercedes in its announcement of DPF technology for diesel cars, an important development given the current juxtaposition of increasing regulation and heightened demand for diesel-run vehicles.

Because the use of platinum can form sulphate emissions, catalyst-based systems require ultra low sulphur fuels and can therefore be used only in areas where such fuels are available.