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Pressure differential sensor lines
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Pressure differential sensor bracket
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Pressure differential sensor
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Exhaust hanger insulators
DPF filter system consists of the following components:
- Diesel particulate filter (DPF)
- Pressure differential sensor
- Temperature sensor
DPF
The DPF reduces the pollution generated by diesel vehicles by filtering soot particles out of the exhaust gases.
Pressure Differential Sensor
The pressure differential sensor monitors the pressure drop within the DPF.
Temperature Sensors
The exhaust temperature sensor monitors the catalyst temperature. The DPF temperature sensor monitors the pre-DPF temperature. These signals are sent to the powertrain control module (PCM).
Regeneration of the DPF
Soot particles can accumulate in the post DPF exhaust tailpipe. The accumulation of the soot particles should not be considered a concern, as the DPF is not 100% efficient at filtering the soot particles.
During the regeneration process, it is possible that white smoke may be emitted from the exhaust tailpipe. This is an inherent by-product of the regeneration process and should not be considered a concern.
The pressure differential sensor is connected to the DPF by the pressure differential sensor lines to monitor the pre-pressure and post-pressure of the DPF. The pressure differential sensor converts these measurements to a signal voltage, which is then sent to the PCM to be used as part of the decision of whether to apply the regeneration process or not.
The PCM will choose the optimum time for the regeneration of the DPF. Under normal operating conditions the regeneration process occurs when the PCM has calculated that the DPF requires regeneration and that predetermined vehicle conditions are met (for example coolant temperature, vehicle speed and engine load).
Manual regeneration of the DPF
If the DPF becomes blocked the pressure differential sensor will register a high pressure diagnostic trouble code (DTC) with the PCM, the malfunction indicator lamp (MIL) will be illuminated and the limp home mode activated.
A blocked DPF can be a result of:
- Excessive soot particles production
- Multiple failed regeneration events
- Mechanical or electrical failure of a related system or sub-system (for example EGR valve stuck open, charge air system leak, fuel injectors)
The manual regeneration of the DPF can be used to clear the soot particles from the DPF. For additional information, refer to WDS.
Muffler
