Diesel Particulate Filter (DPF) Solution

*Please note that we only offer DPF solutions for Off-Road Usage only. Although it is not illegal to remove a DPF filter from your vehicle, it is an offence under the Road vehicles (Construction and Use) Regulations (Regulation 61a(3))1 to use a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet. Removal of a DPF will almost invariably contravene these requirements.*

WHAT IS A DPF?

A DPF (Diesel Particulate Filter) also known as FAP on some French vehicles, is a device fitted to the exhaust system of modern diesel vehicles to reduce emissions and meet European emission standards. It does this by trapping Soot from the exhaust gasses as they flow out of the exhaust.

They have been in common use in passenger cars and light commercials from around 2003 in preparation for Euro 4 regs in 2005. Peugeot, Renault, and BMW were early adopters. Euro 5 emissions regulations in 2009 made it compulsory for diesel cars and light commercials to have a DPF fitted, and the 2014 Euro 6 introduced further emissions restrictions.

As with any type of filter, a Diesel Particulate Filter needs to be cleaned regularly to function properly. In this instance the process is known as regeneration, where the soot is burned off – which you may notice as a blast of white smoke emanating from the exhaust – leaving an ash residue within the DPF.

PROBLEMS ENCOUNTERED WITH DPF

If regeneration doesn’t function properly it leads to a build-up of soot affecting performance and fuel economy, left unattended this will result in a Blocked DPF which can ultimately cause very expensive damage to other engine components. A blocked DPF is also potentially dangerous as it can cause overheating in the exhaust system and cause a fire risk. To prevent this damage most new vehicles will go into “Limp Mode” at this stage, meaning the vehicle will have minimum power barely sufficient to crawl home.

For regeneration to take place it requires the vehicle to be driven regularly at some speed on open roads e.g. motorway driving, typically driving at around 2500 RPM for approx. 15-30 mins at least once a month, this will keep things working.

Many diesel vehicles are used primarily for short journeys, rarely getting up to the full operating temperature that a regeneration needs; and over time a DPF will suffer from an accumulation of ash residue whether it has been correctly regenerating or not. For this reason, a DPF is classed as a serviceable item by vehicle manufacturers, not covered under warranty. DPF systems therefore require proper maintenance.