“We are the one of the best mobile DPF cleaning specialists in Milton Keynes

Signature only uses the best quality products on the market, all of our DPF and EGR products have been approved by many leading vehicle manufacturers. Aston Martin. Mercedes Benz, Jaguar and Citroen plus many more.

What is a DPF?chevrolet-cruze-20td-z20s1-cat-dpf-combined-1-11

Located within the exhaust system, a DPF (Depollution Filter) captures small soot particles, preventing them from being expelled into the atmosphere. As with any filter it needs emptying periodically and this is done automatically, by burning up the particulates in a process called regeneration.

Regeneration is either passive or active.

Passive regeneration

Passive regeneration takes place automatically on motorway or fast A-road runs when the exhaust temperature is high. Because many cars don’t get this sort of use vehicle manufacturers have had to design-in ‘active’ regeneration where the engine management computer (ECU) takes control of the process.

Active regeneration

When the soot loading in the filter reaches a set limit (about 45%) the vehicle’s ECU will initiate post combustion fuel injection to increase the exhaust temperature and trigger regeneration. If the journey is too short while the regeneration is in progress, it may not complete and the warning light will come on to show that the filter is partially blocked.

It should be possible to complete a regeneration cycle and clear the warning light by driving for 10 minutes or so at speeds greater than 40mph.

Symptoms of active regeneration

During active regeneration you may notice the following symptoms:

If the regeneration is unsuccessful due to an insufficient driving cycle the extra fuel injected into the cylinders will not burn and will drain into the sump.  As a result, oil quality will deteriorate and the level will rise.  Most DPF equipped engines will have an oil quality/viscosity sensor but it is important that you check that the oil level does not increase above the maximum level on the dipstick as diesel engines can run on their own oil if the level is excessive often to the point of destruction.

If you ignore the DPF warning light and keep driving in a relatively slow, stop/start pattern, soot loading will continue to build up until around 75% when you can expect to see other dashboard warning lights come on too. At this point driving at speed alone will not be enough and you will need to take the car to a dealer for ‘forced’ regeneration.

Forced regeneration

Forced regeneration is required where `Active` regeneration criteria have not been met or where soot levels have increased within the DPF to a point where normal regeneration cannot be performed: typically around 70% soot loading.  At this point the vehicle will enter a ‘restricted performance’ mode to prevent further damage.  If left the soot loading will keep rising.

At this level of soot loading a diagnostic tool must be used to force regeneration. Above around 85% soot loading regeneration can no longer be performed on the vehicle and the DPF will need removing to be cleaned or replaced.

What can prevent normal regeneration taking place?



Cleaning the Diesel particulate filter instead of replacing: Efficient & fast.


The electronic indicator lights, the vehicle has no more power and extremely high fuel consumption? The diesel particulate filter has only a limited capacity to store particulates. From a certain amount of soot, the soot particles must be burned in a regeneration process to CO2 and ashes. Different reasons can mean the regeneration process does not start and in consequence the DPF gets clogged with soot particles.   maxresdefault


Possible causes:


Signature uses a patented particulate filter cleaning system with which clogged particulate filters can be cleaned in an installed condition, rapidly, simply and significantly more economically than replacing them.

An overloaded DPF: That is expensive.

For replacement of the part customers have to pay a lot of money. For a new diesel particulate filter between £600 and £4000. In addition a prolonged stay in the workshop and a rental car has to be organised. Signature will clean your DPF filter for the fraction of the cost as a replacement DPF and get you back on the road the same day.
Cleaning instead of replacing

Optimal customer service




Loss of power, rough idle and elevated emissions result in more and more expensive repairs. The increasingly common causes of this are dirty or stuck EGR valves and carbonised parts in the intake and exhaust system.

SOLUTION:  EGR System Cleaner

The innovative XFoam technology dissolves stubborn contamination in motor vehicle intake and exhaust system very quickly. The outstanding spraying and wetting characteristics ensure the product quickly takes effect, does a very good job of dissolving dirt and has excellent flow properties. This is the optimal product for cleaning EGR Valves and small/large components in intake and exhaust systems.



DPF Removal is not a legal option

It is suggested from time to time that the answer to failed DPF regeneration is get the DPF removed from the exhaust system rather than pay to get it repaired/renewed.  Indeed there are companies advertising just such a service including reprogramming of the engine management software, but is it legal?

DPFs are fitted to meet European emissions regulations designed to reduce vehicle emissions of particulate matter (soot) associated with respiratory disease and cancer.

According to the Department for Transport, it is an offence under the Road vehicles (Construction and Use) Regulations (Regulation 61a(3)) 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, making the vehicle illegal for road use.


From February 2014 the inspection of the exhaust system carried out during the MOT test will include a check for the presence of a DPF. A missing DPF, where one was fitted when the vehicle was built, will result in an MOT failure.

With an original equipment DPF removed from the exhaust the car may or may not pass an MOT smoke test – a Euro V (September 2009 diesel) is more likely to fail than one designed to comply with earlier emissions standards.