DPF Solutions FAP and EGR Explained.


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 while letting the gasses flow through the system.

DPF Unit

As with any type of filter a Particulate Filter needs to be cleaned regularly to function properly. With DPF’s this is done by a process known as Regeneration which involves a combination of a Catalyst function in the system and burning the soot to gas at a very high temperature leaving behind an Ash residue within the DPF. Regeneration should be an automatic process taking place in the normal use of your vehicle, you may have noticed this in the form of a blast of white smoke form the exhaust on occasions.


If regeneration doesn’t function properly it leads to a build up of soot affecting performance and fuel economy, left unattended this will result in a Blocked DPF which can ultimately cause very expensive damage to other engine components. A blocked DPF is also potentially dangerous as it can cause overheating in the exhaust system and cause a fire risk. To prevent this damage most newer vehicles will go into “Limp Home” safety mode at this stage, meaning the vehicle will have minimum power barely sufficient to crawl home. For regeneration to take place it requires the vehicle to be driven regularly at some speed on open roads e.g. motorway driving, typically driving at around 2500 RPM for approx 30mins at least once a month, this will keep things working.

Even if the regeneration functions as it should, over time the Ash Residue will build up in the DPF and have the same affect ultimately resulting in a blocked DPF. For this reason a DPF is classified as a Serviceable Item by the vehicle manufacturers like brake pads or air filters etc and not covered under warranty. DPF systems therefore need to be maintained properly.


If your DPF warning light or Anti-Pollution warning is on, please do not ignore it (typical dash warning symbols below). Get professional advice, consider your options carefully and attend to the problem. Leaving it will ultimately cost you much more in additional repair bills and it can be dangerous.

Common DPF Lights

By the time your DPF warning lights are visible your DPF will already be significantly blocked. Forced regeneration by a garage or a “blast down the motorway” is not likely to cure the problem, these only work as preventative maintenance. So at this stage realistically you have the following 3 options:-

DPF Replacement – Dealers can replace the DPF but at a cost. They carry out full diagnostic checks, replace the DPF unit, recalibrate the ECU, reset the warning lights and run a road test.

DPF Solutionl – Team Valley Tuning have a DPF solution meaning you will not have any future DPF blockage problems. This is the cheapest option. We carry out full diagnostic checks, diconnect the DPF unit, carry out the modifications and refit the modified unit, recalibrate the ECU, reset the warning lights and run a road test. We can also add a remap at the same time to improve fuel economy and performance, ask Paul about Remap package. On completion there is no visible changes to the system and no excessive smoke. Our solution is reversible so you can refit a non-modified DPF again in future if you wish.

Prices starting from only:-


*price includes DPF solution, DPF delete from ecu and Tuning file.


It is not illegal to remove the DPF.

It is an offence to use a vehicle on the road that no longer complies with the emissions standards it was designed to meet. This however means that changing any part of the exhaust or emissions system with a part other than the vehicle manufacturer’s original part may change the emissions meaning it could be an offence. In reality emissions testing outside the London Emissions Zone (LEZ) is normally limited to the standard MOT test.

From February 2014 the inspection of the exhaust system carried out during the MOT will include a visual check for the presence of a DPF, if fitted as standard equipment.

When Team valley Tuning carries out DPF solution work we retain the original assembly and on completion there is no visual difference, this way you have the option of reinstalling a replacement DPF in future if you wish.

However Team Valley Tuning can not be held responsible for your vehicle failing it’s mot. When undertaking this modification you agree that we (Team Valley Tuning) can not be accountable or liable in any way.


Modern engines recirculate some of their exhaust gases back into the engine with the aim of reducing emissions. This is the is the main benefit of the EGR system. The downside is that exhaust fumes containing carbon deposits are constantly being recirculated through the engine through time causing a build-up of carbon deposits in the intake manifold etc.

These deposits sometimes contribute to the failure of the EGR system itself. Replacement EGR valves can be expensive and in the case of high mileage engines the continual carbon build up can eventually lead to total engine failure.


Our EGR Solution and reprogramming of the engine management ECU results in lowered engine temperatures, improved throttle response and economy and also can lengthen engine life by reducing oil contamination and carbon deposits.


At present it is not illegal to remove the EGR valve and it doesn’t form part of the MOT test. Whether this might be tightened up in the future, no one knows and our best guess that even if it is, then it will not be applied retrospectively.

Since the EGR system recirculates a portion of exhaust gases, over time the valve can become clogged with carbon deposits that prevent it from operating properly. Clogged EGR valves can sometimes be cleaned, but replacement is often necessary if the valve is faulty.


You can call Paul on our telephone number: 0191 482 5936. Paul will be happy to help you. OR You can contact Team Valley Tuning and request a quote Here. We give 30 day money back guarantee, in case you are not satisfied with our service.