See also:

Diesel particulate filter system
Complementary to the catalytic converter, this filter makes an active contribution to the preservation of air quality by the retaining of the unburnt pollutant particles. Black exhaust fumes are t ...

Ventilation
Air intake Make sure that the exterior air inlet grille at the base of the windscreen is clean (free of dead leaves, snow etc.). If washing the vehicle with a high pressure jet, take care to avo ...

Screen in instrument panel
...