1 Connection โ exhaust gas temperature sensor โ diesel particulate filter
2 Pipes to diesel particulate filter differential pressure sensor
3 Diesel particulate filter and catalytic converter housing
The diesel particulate filter of the 1.6L Duratorq-TDCi (DV) engine is downstream of the catalytic converter in the flow direction of the exhaust gases. Oxidation catalytic converter and diesel particulate filter are combined in one housing. The particulate matter contained in the exhaust gas is deposited in the diesel particulate filter. The pressure drop across the particulate filter (measured via the diesel particulate filter differential pressure sensor) is an indicator for the soot load of the filter. The soot load capacity of the diesel particulate filter is limited, however, so that it has to be regenerated at regular intervals (burning/oxidation of the diesel particulates).
After regeneration, ash residues that have formed from the fuel additive, engine oil and fuel remain in the diesel particulate filter. These constituents cannot be further converted and can only be deposited in the diesel particulate filter up to a certain degree. This means that the diesel particulate filter must be replaced at prescribed service intervals.
1 Exhaust gas from engine
2 Oxidation catalytic converter
3 Diesel particulate filter
4 Cleaned exhaust gas
The diesel particulate filter is a honeycomb structure, the walls of which are made of porous silicon carbide In addition, the individual ducts are sealed at one side and offset to each other.
After combustion has occurred, some diesel particulates may still be present in the exhaust gas. As part of the filtration process, the exhaust gases loaded with diesel particulate matter flow into the diesel particulate filter
and are then forced to flow through the porous walls as a result of the offset position of the sealed channels.
The build up of diesel particulate matter in the intermediate chambers of the porous walls increases the filtration effect still further.