If you own a relatively modern diesel car then you may have heard of a diesel particulate filter or DPF for short. All diesel cars from 2009 were fitter with one and many models prior to this date. The job of the diesel particulate filter is to convert all the soot that is produced in the exhaust system in to tiny particles by burning them up.
This process is known as regeneration and in order for it to happen, the car engine needs to be a certain temperature. This temperature is only usually achieved by taking the car on long journeys where you can get up to a decent speed. If you often only use the vehicle for short journeys then it is likely that the car will not get hot enough for this process to happen and your DPF filter will then become blocked. If this does happen, you may find yourself being charged in excess of a thousand pound to rectify it.