Ca sa lamurim treaba cu regenerarea, adaug in continuare un paragraf elocvent din documentatia BMW: "RegenerationThere are two kinds of regeneration: Continuous regeneration: This form of regeneration takes place during normal driving. At exhaust-gas temperatures of between 280-350°C, continuous regeneration takes place in the form of a slow oxidation process. The soot particles cannot be incinerated until the exhaust gases reach the required temperature.Periodic regeneration: Periodic regeneration is performed automatically by the DDE after no later than 1000 km (600 miles). On vehicles with many short-distance drives, periodic regeneration already starts taking place after just 400 - 800 km (250 - 500 miles). For regeneration, the intake air is reduced by the throttle valve. One or two post-injections are performed. This increases the exhaust-gas temperature to about 600 °C. The soot is incinerated with the residual oxygen. The periodic regeneration is performed at all speeds. The most efficient method is regeneration at a constant speed in excess of 60 km/h (38 mph) over a period of 20-30 minutes. The DDE calculates the time for periodic regeneration from the following values: -average distance travelled -average driving speed -temperature in the diesel particle filter -values from the exhaust gas pressure sensor The last successful regeneration can be read out by the diagnosis system The following conditions must be fulfilled for a regeneration: -The coolant temperature must be in excess of 75 °C -the exhaust-gas temperature before the diesel particle filter must be greater than 240 °C -there must be enough fuel (fuel reserve indicator light is not lit up). Whenever the reserve lamp lights up, the regeneration process is suspended. -no fault codes from the air mass system, exhaust emission system and sensors must be saved in the DDE -The fault codes 480A / 245700 (from F01) and 481A / 245800 (from F01) must display the status "currently not present" -Constant driving speed above about 60 km/h (approx. 38 mph). The optimum speed is about 100 km/h (approx. 60 mph)."