Similar to other types of filter the diesel particulate filters will work best when cleaned out regularly. With these filters the caught soot needs to be burnt off at a high temperature so that only a small amount of ash is left. This process can be carried out in two ways. The first is a passive process whereby the soot is burnt off due to the high temperatures in the exhaust when the car is driving at high speeds over a period of time. This would occur for example if the car were driven on the motorway for some time.
