In 2004, a new range of Pumpe-Düse (PD) Unit Injector diesel engines was offered. The design employed unit injectors along with additional electronics and emissions equipment to meet emissions standards in Europe and North America, and is more complex than diesel engines previously offered. To accomplish the task of producing sufficient power while meeting emissions standards, the “PD” technology injects fuel directly into the combustion chamber at pressures up to 2,050 bar (30,000 psi). The purpose of the high pressure is to promote fine atomisation of the fuel, which supports more complete combustion. To reduce noise, the engine employs a “pilot injection” system that injects a small amount of fuel prior to the main injection. All of the new generation of diesel engines required a special motor oil to meet Volkswagen oil specification 505.01 (or newer), noting that serious damage to the engine, particularly the camshaft and injectors, will result if oil not meeting this standard is used.