Should I Remove My Diesel Particulate Filter?
Diesel Particulate Filters (DPF's sometimes called FAP's) are fitted to vehicles to reduce the sooty particle produced by diesel engines which penetrate deep into the lungs and are being increasingly blamed for an increase in heart and respiratory disease.
Some DPF's require an additive in order to burn off the harmful soot particles and some are fitted closer to the engine so that the exhaust gasses themselves remain hot enough to burn off the carbon soot particles.
The DPF itself has a honeycombed interior like a catalytic converter made of silicon carbide. This is contained in a metal casing.
The honeycombed centre traps the particles of soot not burned off or not cleared by additive, until they are full and the filter cannot trap anymore. This is when the DPF goes through the "Regeneration process". This process turns the soot into a very small volume of ash which remains in the filter.
Passive regeneration
The passive re-generation process should automatically happen when a vehicle is on a motorway run when the exhaust temperature is high but many vehicles do not travel on motorways often enough to force this passive regeneration.
Active regeneration
It should be possible to start an active regeneration and clear the warning light whilst driving at a speed of at least 40mph for around 10 minutes. Many drivers ignore the warning lights until the filter is too full for a regeneration to take place.
This is when the vehicle will need to be seen by a professional. The light normally is triggered when the filter is 55% full, the soot loading will continue until it is 75% full at this point the engine management light will illuminate, the vehicle will not now be performing as it once did.
The only solutions at this stage are to replace the filter (usually 1,500 or more) or to use a professional cleaning service.
Imminent new MOT legislation means that all original emissions reduction equipment that is removed or bypassed by damaging will fail the MOT test.
We are hearing more and more frequently that when a DPF has been removed rather than cleaned or replaced then the back pressure that the turbo relies on is altered. this means that the turbo charger performance is seriously affected which will lead to its inevitable early failure. secondly, the engine ecu needs to be re-mapped when removing the dpf. once re-mapped this procedure is irreversible and when legislation comes into force not only will you be purchasing a new dpf you will also have to replace the ecu at huge cost. Removal and bypassing by damaging will also have a negative effect on the residual value of the vehicle.
Some DPF's require an additive in order to burn off the harmful soot particles and some are fitted closer to the engine so that the exhaust gasses themselves remain hot enough to burn off the carbon soot particles.
The DPF itself has a honeycombed interior like a catalytic converter made of silicon carbide. This is contained in a metal casing.
The honeycombed centre traps the particles of soot not burned off or not cleared by additive, until they are full and the filter cannot trap anymore. This is when the DPF goes through the "Regeneration process". This process turns the soot into a very small volume of ash which remains in the filter.
Passive regeneration
The passive re-generation process should automatically happen when a vehicle is on a motorway run when the exhaust temperature is high but many vehicles do not travel on motorways often enough to force this passive regeneration.
Active regeneration
It should be possible to start an active regeneration and clear the warning light whilst driving at a speed of at least 40mph for around 10 minutes. Many drivers ignore the warning lights until the filter is too full for a regeneration to take place.
This is when the vehicle will need to be seen by a professional. The light normally is triggered when the filter is 55% full, the soot loading will continue until it is 75% full at this point the engine management light will illuminate, the vehicle will not now be performing as it once did.
The only solutions at this stage are to replace the filter (usually 1,500 or more) or to use a professional cleaning service.
Imminent new MOT legislation means that all original emissions reduction equipment that is removed or bypassed by damaging will fail the MOT test.
We are hearing more and more frequently that when a DPF has been removed rather than cleaned or replaced then the back pressure that the turbo relies on is altered. this means that the turbo charger performance is seriously affected which will lead to its inevitable early failure. secondly, the engine ecu needs to be re-mapped when removing the dpf. once re-mapped this procedure is irreversible and when legislation comes into force not only will you be purchasing a new dpf you will also have to replace the ecu at huge cost. Removal and bypassing by damaging will also have a negative effect on the residual value of the vehicle.
