In the ever changing world of motor vehicle development comes with it stricter controls on emission devices. Euro influences in this sector have been apparent for years in the petrol market with the increasing standards of factory catalytic converters. So too, we are seeing the influence on how manufacturers are cleaning up emissions in diesel vehicles and this is being done in a very big, expensive and complicated way.
A Diesel Particulate Filter (DPF) captures and stores exhaust soot reducing dangerous emissions from diesel vehicles. Running in conjunction with a diesel catalytic converter, their aim is to capture dangerous diesel by-products and contain them within the unit.
The issue with this is that the build up of soot in the unit needs to be burned off. This happens via a regeneration process. This regeneration process can happen in a number of different ways, dependant on the make and model of the vehicle and can come as quite a shock to consumers who didn’t even know it existed. The vehicle will usually indicate that the unit is full by a warning light appearing on the dash. This may vary from vehicle to vehicle, so check your owner handbook for further details.
Regeneration
There are three types of Diesel Particulate Filter (DPF) regenerations which can occur.
The first is passive regeneration which happens when high exhaust temperatures are reached during intensive use, normally either long spells of motorway driving or hill climbing. The passive regeneration will automatically burn off the trapped diesel particles.
The second is an active regeneration of the DPF, where the ECU is programmed to initiate post combustion fuel injection to increase the exhaust temperature and burn away diesel particles.
The third type of regen is a forced regen. Forced regeneration is performed using a scan tool in a mechanical workshop. A standard component of servicing a modern diesel vehicle.
During any of the regenerations listed, if the regeneration is cancelled due to interference, the vehicle will automatically attempt to regenerate again at its earliest convenience. This cycle will only allow 3 stoppages before it will display an engine light permanently. If they continue to drive, it will force the vehicle into limp mode.
Replacement of a Diesel Particulate Filter (DPF)
Of course, there will come a time where regeneration will not be possible and the unit will be full and need replacement. During these ‘regeneration’ cycles, a DPF is not emptied entirely. Waste that is not able to be burnt off (ash) compresses and collects within the filter.
In this instance, the unit will need to be replaced. This can be done in two ways. Either through your local dealer as a genuine spare part or via an aftermarket product through an exhaust expert. The repairer will carefully carry out a number of steps (including a forced regeneration) when diagnosing a blocked DPF.
Replace you DPF with a quality product only
Type approval is a UK standard of manufacture that allows aftermarket manufacturers to obtain certification for their devices to be fitted to vehicles and retain factory standards. Type approval provides confirmation that production and samples of a design will meet specified performance standards. For emissions components this encompasses noise, emissions and balanced back pressure, which have a strong influence on maintaining engine performance and fuel efficiency. Type approval ensures that an aftermarket component will reach, or exceed the performance standard of the corresponding OE part.
Type-approval then, is a certain guarantee that an end user will receive a product of OE equivalent performance attributes.
An OEM equivalent aftermarket Diesel Particulate Filter (DPF) provides the user with high reliability if properly installed on a vehicle. Many inferior replacements will feature a lower level of quality and do not meet type approval standards, in turn offer an inferior product to the customer and one that does not meet OE standards. This can be a costly exercise to the end user.
While Type approval standards are not compulsory in Australia, we highly recommend that when replacing your DPF that you choose a supplier that meets these standards. A DPF is after all an integral and in some cases, an expensive component of your vehicles exhaust system.
For any questions or concerns regarding your DPF, call an expert at Kirrawee Mufflers.
