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 (Particulate Matter - PM) 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.
DPFs have been in common use in passenger cars and light commercials from around 2003 in preparation for Euro 4 regs (2005), with Peugeot, Renault and BMW being early takers. Euro 5 (2009) made it compulsory for diesel cars and light commercials to have a DPF fitted and Euro 6 2014 will tighten this up further.