Skip to content

Removal of DPF filter will cause car to fail MOT from February

Over the last few years cars have been forced to clean up their act. Emissions regulations have got tougher and technologies have had to be found to keep up. At the same time, fuel has got ever more expensive and more and more motorists have bought diesels because of their better fuel economy figures.

Over the last few years cars have been forced to clean up their act. Emissions regulations have got tougher and technologies have had to be found to keep up. At the same time, fuel has got ever more expensive and more and more motorists have bought diesels because of their better fuel economy figures. This raises the thorny problem of diesel particulate filter (DPF) removal.

The trouble with some of the technologies introduced to meet emissions regulations is that they are sometimes overly complex and not very good. The DPF is a good example of this. If it wasn't for the emissions regulations, no manufacturer would dream of adding such a component to their cars. It is expensive, reduces power and can cause serious problems when it goes wrong. It is also imperfect in its operation. The DPF works by trapping soot particles in the exhaust and then burning them off. In order to do this effectively, the car needs to drive at a constant speed for 15 minutes or more. Stop-start urban motoring typical of many drivers on short commutes and the school run will not achieve this. That means that the particulates can clog the DPF and cause major problems – and garage bills that typically exceed £1,500. A DPF will typically need replacing after something more than 80,000 miles. This, too, is a major expense.

On the other hand, there are plenty of companies around who will remove your DPF and alter your car's engine management system so that it doesn't look for the component. This typically costs a few hundred pounds. Because the DPF serves no other purpose and actually hampers the performance of your car, many motorists have been tempted to get rid of it.

For those who have gone down this road, the day or reckoning is approaching. From February, a car that is meant to have a DPF but doesn't will fail its MOT. This is going to leave many motorists with an expensive bill for replacement or an illegal car. A better option than illegal removal may be cleaning. Online companies offer this service at a fraction of the price of a new DPF. Another option is to buy a third party DPF, which can cost around 35% of the price of a branded one. For those who have already succumbed to temptation, this last option may be the only viable one. It is just unfortunate that they have already shelled out for removal.

Posted by on

Back to January 2014

Back to top