The Diesel Particulate Filter (DPF) system, consisting of a filter assembly, two Exhaust Gas Temperature Sensors (EGTS) and a Differential Pressure Sensor (DPS), prevents Particulate Matter (PM) from being discharged into the atmosphere. The filter is integrated in the catalytic converter assembly and has a honeycomb cell structure for filtering out PM from the exhaust gas. When the exhaust gas passes through the DPF, PM is collected in the DPF and other substances (CO2, NO, etc.) are discharged into the atmosphere through the muffler. The collected PM in DPF is called "soot".

If there is excessive soot in the DPF, it must be regenerated. ECM calculates the amount of soot by using the DPS signal, vehicle mileage or simulation data. If the ECM determines that the DPF needs to be regenerated, it will perform "Regeneration Procedure" when the vehicle enters the predetermined state (Regeneration Mode).

To burn off the soot, ECM injects additional fuel in the cylinders during the exhaust stroke (two Post Injections) and increases the exhaust gas temperature to combustion temperature (above 600℃). During this, soot is burnt and its ash only remains in the DPF as a result of the combustion.

5.

Engine Coolant Temperature: Over 40℃