Diesel Particulate Filter (DPF)
Posted: August 03rd 2017
Since its introduction in 2001, the Diesel Particulate Filter (DPF) has been the subject of controversy
DPFs are a filter device, constructed of a metal casing containing an internal ceramic monolith.
The regeneration cycle is a controlled burn-off that happens inside the DPF where soot is burnt through to form less harmful gas and fine ash which remains in the DPF.
Regeneration tends to occur when the DPF reaches a high temperature for a prolonged period, such as motorway driving.
The MOT test includes a DPF check for diesel vehicles if the component was fitted from new – so why are some motorists and garages illegally removing DPFs from vehicles?
Many owners of diesel vehicles who only make short journeys will notice that the DPF fills quickly and does not regenerate.
“The exhaust system cannot reach a suitable temperature on these journeys, so the soot is given no opportunity to reduce, and so clogs the monolith.
“Some motorists will assume that it’s the component that is faulty and may opt to remove the DPF entirely as clogging continually reoccurs.
DPF removal ‘black market’
“This is illegal and will actually start to damage the car as well as adding highly carcinogenic pollutants into the atmosphere.
“The situation can be avoided by simply taking the vehicle on a long journey once a month, providing an opportunity for the DPF to burn off the excess soot
It is now a legal requirement for a DPF to be present on a road going vehicle if it was fitted from new.
The absence of a DPF on an applicable diesel vehicle will result in an automatic MOT test failure.
FitnFix Auto have experience in dealing with Dpf issues and we will be happy to help if issues occur.