The diesel particulate filter, available as wall-flow filter or flow, are necessary to only about 60 nm to 120 nm in size soot particles to filter resulting from the combustion in modern diesel engines. This diesel particulate filters are not comparable with the usual catalysts for petrol cars. Diesel particulate filter to keep back a large portion of the solid contaminants in the filter system and then burn them using special technology in driving regeneration. Wall-flow filters are usually installed as standard. They are very effective and can even filter out fine particles. The exhaust gases are led here by a porous filter wall, whence is derived the name here wall-flow filter. The clogging of the filter is prevented by a regeneration system that is controlled by the different pressure conditions while before and after the filter. When the full filter, the particles are then burned off during driving and excreted as a gas. The driver remembers nothing of this operation, a change in performance is not detectable. Thus, the filter is almostmaintenance. Flow diesel particulate filters are offered in general only for retrofitting. They are not as effective as the above-described wall-flow filter, but they are cheaper and have the advantage of not turn out that the increase in wall-flow filter fuel consumption figures as too high. Here, the emissions are not forced through a filter system but is managed by a certain, very sophisticated direction of flow through the filtration system, whereby the fine particles remain attached to the filter walls. These are continuously regenerated by thehigh exhaust gas temperatures and converted into gas. Both diesel particulate filters – systems are very good for reducing particulate emissions from modern diesel engines. Reduce diesel particulate filter also the car tax and increase the resale value of the vehicle. The retrofit diesel particulate filter is used in many shops have already priced competitively.