Diesel Particulate Filters (DPF) and the Environment
Diesel Particulate Filters (DPF) as well as the EnvironmentReducing diesel soot emissions by 80%:
The target is an 80% decrease in diesel particulate (soot) emissions, but the technology's not without troubles; roadside assistance patrols are already being called to automobiles with the particulate filter warning light illuminated, which normally indicates a partial blockage of the DPF filter.
Certainly, changes to styles that were driving may be required from these emission-reducing systems for maximum gain.
How do the filters work?:
Diesel Particulate filters (DPF) or 'traps' do only that, they catch bits of soot in the exhaust.
For a DPF this process is called 'regeneration'; the accumulated soot is burnt off at high temperature http://www.dpfcleaningsolutions.com to make only a tiny ash deposit. Regeneration could be either passive or active.
Passive regeneration
Passive regeneration occurs automatically on motorway-kind runs when the exhaust temperature is high. Many autos do not get this kind of use though so manufacturers have to design-in 'lively' regeneration where the engine management computer (ECU) takes control of the procedure.
Lively regeneration
In case the journey's a bit stop/start the regeneration may not finish as well as the warning light will illuminate to show that the DPF is partially blocked.
It should be possible to begin a regeneration that is complete and clear the warning light by simply driving for 10 minutes or so at speeds greater than 40mph.
Should you keep driving in a comparatively slow and ignore the light, stop/start design when you are able to expect to see other dash warning lights illuminate too. At this stage driving at speed alone won't be sufficient and also the car will need to attend a dealer for regeneration.
Expensive repairs:
If warnings are still blown off and soot loading continues to increase then the most likely outcome is going to be a new DPF costing around GBP1000.
Mainly town driving that is established:
If lease automobile use or your own car use is largely town-established, stop/start driving it'd not be unwise to choose petrol rather than risk the hassle of incomplete DPF regeneration.
DPF additives:
The most common form of DPF is found very near the engine so that passive regeneration is potential where exhaust gases will still be relatively hot and features an incorporated oxidising catalytic converter.
There's not consistently space close to the engine though so some producers use another kind of DPF which relies on a fuel additive to lower the ignition temperature of the soot particles in order that the DPF could be located farther from the engine.
The additive is kept in a separate tank and is automatically blended with the fuel whenever you fill up. Tiny amounts are demanded though so a litre of additive should treat around 2800 litres of fuel, enough to cover 25,000 miles at 40mpg.
With this specific sort of DPF regeneration will be started by the ECU every 300 miles or so depending on vehicle use and will take 5 to 10 minutes to complete. You should not notice anything other than perhaps a puff of white smoke from the exhaust when the procedure is completed.
AA encounter:
The AA has seen evidence of DPF systems failing to regenerate - even on autos - that are used mainly on motorways. Their judgment is that on autos with a very high sixth gear engine revs are excessively low to produce adequate exhaust temperature, but occasional more challenging driving in lower gears should be sufficient to bum off the soot in such cases.
Examine the handbook: