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FAP - DPF PARTICLE FILTER - What is the particulate filter?

The particle filter also called FAP or DPF is an element that is placed in the exhaust system and later burns the particles to convert them into carbon dioxide and water mainly.
FAP is a particulate filter designed and patented by Citroën-Peugeot group which regeneration system is characterised by the using of an additive, cerium oxide 
The combustion of the PM10 naturally takes place at around 600-650°C but exhaust gas only reaches 200°C maximum. It’s necessary to raise the temperature with a post-injection of fuel: this is the moment when the cerium comes into play to lower the ignition temperature of the soot particles to 450°C, speeding up the regeneration and protecting the filter from a potential dangerous thermal stress.
The cerium oxide facilitates the combustion of the particulate but it does not burn together with it, on the contrary it sediments inside the filter.

Filter without additives
It is placed near the engine to take advantage of the higher temperature of the gases that come out of the engine. When this temperature is reached, the particles can be combusted without the need for an additive.

filters with additive
In this case, the filter is placed further away from the engine and to reach the combustion temperature of the particles, an additive is needed so that it can work correctly. This additive is introduced into a tank and has a range between 60,000 and 100,000 km.

Filters with AdBlue - SCR
In this case, before the filter, an injector is mounted that injects the AdBlue so that the filter can be cleaned. This type of filter is unreliable due to problems with the AdBlue system itself.

FAP/DPF regeneration
The regeneration process is connected to the backpressure value, that is the difference between the incoming pressure of the air in the filter and the outcoming pressure: the more the filter is clogged, the higher is the difference, until the car recognizes the limit value and let the regeneration begin. The most common particulate filters are FAP and DPF which are different in functioning but especially in the regeneration strategy.
In order to regenerate, the FAP needs to maintain a high rpm speed for a certain time. For example, circulate at 70-80 km/h at 3000-3,500 revolutions for a while. If it has reached a high saturation point, a forced regeneration must be carried out. If the saturation level is too high and we continue using the vehicle since we cannot go through the FAP, the gases will not be able to leave the exhaust system and the filter itself will break.

Why does the particulate filter get clogged and damaged
Depending on the use that is given to the vehicle, short trips, exclusive use in the city, driving at low speeds, low quality oil and fuel, engine mechanical problems, etc... Another way to saturate the filter and cause damage is by interrupting repeatedly regeneration cycles.

How do you remove the particulate filter
The removal of a particulate filter has two parts, emptying the ceramic and reprogramming the engine control unit (ECU). It is not recommended to electronically remove a FAP without removing the ceramics.

Is DPF/FAP Removal Legal
There are cases where it is necessary to completely remove the DPF/FAP. Complicated repairs in which to find the problem it is necessary to temporary removal of the filter temporary, competition vehicles, special purpose vehicles, etc.

The removal of the DPF/FAP is at the customer's discretion!
Chip Cars offers global software modification services in various countries around the world. The user must consult the legal regulations in their country.