Why does DPF get clogged

Under normal circumstances, the carbon ash produced by diesel combustion will gradually accumulate in the DPF. When the vehicle is driving on smooth roads such as highways, the high-temperature exhaust of the engine can fully burn these carbon ashes and convert them into carbon dioxide. However, when passive regeneration fails to work effectively, the vehicle may need to adopt active regeneration to clean up carbon ash. This usually requires increasing the engine speed in place to raise the exhaust temperature and achieve the goal of cleaning carbon ash.

Today's engines undergo fine honing treatment inside their cylinders to ensure longer service life and better working efficiency. This process will carve a delicate mesh pattern on the cylinder wall, which is mainly used to store engine oil and enhance lubrication effect.

When the combustion process inside the cylinder occurs, the oil in the mesh pattern will be instantly heated and participate in combustion. During this process, the engine oil may produce some ash particles, which will be discharged together with the exhaust gas. It is worth noting that in addition to base oil, engine oil also contains various additives, which may contain metallic components. Therefore, during the combustion process of engine oil, some ash may not be completely processed through combustion, and these components may ultimately only enter the post-treatment system.