Why do you need a particulate filter. Diesel particulate filter for gasoline engine. Identifying a DPF Problem

In the EURO 6c exhaust gas legislation, the limit values ​​for particle mass (PM) and particle count (PN) are even more stringent. The reason for this is the fact that modern internal combustion engines with direct injection do not create such a homogeneous air-fuel mixture as with intake manifold injection.

Therefore, more particles are generated when the fuel is burned. To comply with the limit values, among other things, a diesel particulate filter is installed.

Example: Engine B48 on F22 / F23

Functional description

Installation position of diesel particulate filter for petrol engine

The diesel particulate filter is installed in the place of the middle silencer behind the catalytic converter. In the future, the diesel particulate filter for the gasoline engine will be installed closer to the engine in a common housing with a catalyst.

For unambiguous identification, check the mounting position of the charge pressure sensor.

If the exhaust gas pressure sensor is located at the catalytic converter outlet, the petrol particulate filter is located farther from the engine in the underbody of the vehicle instead of the middle muffler. If the exhaust gas pressure sensor is centered on the catalytic converter housing, the petrol particulate filter is installed closer to the engine.

The installation position of the petrol particulate filter closer to the engine promotes regeneration (burning off the soot), since the required exhaust gas temperatures are more easily achieved.

Design and function of the diesel particulate filter for a gasoline engine

The diesel particulate filter for a petrol engine is permeated by many channels through which the exhaust gas flows. The walls of the diesel particulate filter for petrol engines are porous for the passage of exhaust gases. Particles (soot and ash) settle in the channels.

The channels of the diesel particulate filter for the petrol engine are closed at the edges. Each inlet is surrounded by 4 outlet channels. The particles are deposited in the lining of the intake ports. Particles remain there, which burn when the exhaust gas temperature rises and the required amount of oxygen is required. The cleaned exhaust gas enters through the coated porous walls from the exhaust ducts.

Soot deposits will clog the gasoline particulate filter over time. Therefore, they should be burned. This occurs when the temperature of the exhaust gases exceeds the ignition temperature of the soot. This process is called regeneration. This converts the carbon particles into gaseous carbon dioxide (CO2) by oxidation.

Soot deposits start to burn at temperatures above 600 ° C. Fast and efficient regeneration is only achieved from a temperature of 700 ° C. Since this temperature is only reached at a correspondingly high load, additional measures are taken in addition to natural regeneration (burning of soot with excess air in forced idle mode) of the diesel particulate filter for the petrol engine. So the temperature of the exhaust gases is artificially increased by adjusting the ignition angle. As a rule, the driver is not aware of these processes.

Exhaust gas pressure sensor

In a gasoline engine, compared to a diesel engine, the differential pressure is not measured before and after the particulate filter. Instead, the exhaust gas pressure sensor in the petrol engine measures the exhaust gas pressure in front of the petrol particulate filter and the ambient pressure.

The digital engine electronics (DME) calculates the exhaust gas flow from the boost pressure sensor and other signals (eg air mass).

The exhaust gas flow in conjunction with the measured ambient pressure is used to calculate the exhaust gas pressure downstream of the diesel particulate filter for the petrol engine. The calculated differential pressure upstream and downstream of the petrol particulate filter indicates the loading of the petrol particulate filter. the digital engine electronics (DME) activates regeneration when the load is exceeded.

System functions

Regeneration

Depending on the driving style and service condition of the vehicle, the diesel particulate filter is designed for a mileage of about 240,000 km. When this mileage is reached, the gasoline particulate filter must be replaced with the housing. For this, the exhaust system is removed and a new diesel particulate filter is installed for the petrol engine.

The diagnostic system provides information on the load level. Upon reaching the maximum mileage, a fault memory is recorded, which is read by the diagnostic system. In the vehicle, after reaching the maximum mileage, the service information is not displayed.

To keep the exhaust gas pressure within acceptable limits, the number of regeneration cycles increases as the degree of ash loading of the diesel particulate filter increases. At the maximum ash loading of the diesel particulate filter for a gasoline engine, it is not able to burn out freely. As a consequence, there is a gradual decrease in engine power. If the power derating is exceeded by 30%, the digital engine electronics (DME) activates the emission warning light. The engine management system goes into emergency mode.

Regeneration possibilities

• Normal regeneration: carried out depending on the nature of the movement. Burning off of soot is possible only with excess air in forced idle mode in forced idle mode and at a corresponding high temperature of the exhaust gases.
• Calculated Regeneration: Cyclic regeneration based on movement patterns.
• Regeneration every 10,000 km: set regeneration cycle.

Injection

To improve the parameters of emissions of harmful substances (particles), new nozzles are installed for EURO 6c. The injectors have a new injection geometry. The following graph shows the change:

Service instructions

General instructions

Diagnostic instructions

The diesel particulate filter is diagnosed using the diagnostic system. For this, test modules are provided for the exhaust gas pressure sensor and diesel particulate filter for the petrol engine.

For the service function, the replacement of the diesel particulate filter for the petrol engine must be recorded.

We reserve the right to typing errors, errors and technical changes.

The principle of operation of the filter is based on capturing solid particles that form at the exit from the combustion chamber. The appearance of soot is substantiated by the incorrect ratio of the proportions of the combustible mixture: an overabundance of liquid fuel or a lack of oxygen. Similar situations arise in several cases:

• dirty air filter;
• incorrect adjustment of the valve clearance;
• cams are worn on the camshaft;
• injection timing is not adjusted;
• poor fuel quality;
• leaking injectors.

To clean the exhaust gases from soot particles, a special filter is installed in the design of the exhaust system, which is located between the exhaust manifold and the muffler. The shape of the soot structure resembles a metal flask with a core of multilevel porous walls in the form of cells, on which about 90% of soot particles settle.

Special treatment elements (DPF and FAP) have been developed for environmental standards Euro-4 and Euro-5, with a different operating principle and design features.

Features of the device of the ceramic filter matrix - in closed channels with a tapering octagonal or square section up to 1 mm, on the porous surface of which soot particles are retained. The filter design assumes the presence of sensors: air, temperature and differential pressure.

The design is an open version of the "soot trap", which is optional, but rarely used due to imperfect design.

Closed type soot trap - DPF (Diesel Particulare Filter)

The device is made with a catalytic coating of the matrix honeycomb. Filters must be replaced regularly. Reduction by passive cleaning with superheated exhaust gases is rarely used. To burn out soot, it is necessary to pass crankcase gases with a maximum temperature of up to 600 ° C.

The principle of operation of the DPF type is the oxidation of carbon monoxide in the exhaust and the trapping of soot particles. The operation of the filter is controlled by an electronic unit (ECU), the indication of which is located on the control panel.

FAP (Filtre a Particules)

A special feature of the FAP filter is the active regeneration of the matrix of the purifying exhaust system. The principle is based on the analogy with DPF, but has the function of forced cleaning of the device. An additive with cerium is stored in a special container, which, at the moment of ignition, forms a temperature of up to 1000 ° C. This is enough to burn out soot accumulations in the cells.

Methods for removing the particulate filter

The service life of the filter is designed for vehicle mileage up to 150,000 kilometers. Long-term operation is possible under ideal technical conditions. In practice, the term is reduced several times. This is justified by the use of low quality fuel, which leads to increased contamination of the particulate filter cells.

The first sign of a dirty particulate filter is a noticeable decrease in engine thrust and vehicle acceleration dynamics.

In domestic operating conditions, there is a need to disconnect or remove the filter. Typical signs of particulate filter wear affect vehicle performance:

• floating idle speed;
• increased fuel consumption;
• intermittent engine start;
• the glow plug control lamp is on;
• at idle - uncharacteristic sound (“hiss”);
• it is impossible to develop the maximum engine speed (above 3000 rpm).

You can visually determine wear by the nature of the exhaust - a pungent black tint appears and the abundance of smoke increases.

It consists in reprogramming the controller firmware with an external device, with the appropriate program for the car model.

Re-scanning is carried out on diesel cars, in order to avoid the activation of the emergency mode, when the fault code is diagnosed as complete clogging of the filter. There are several ways to perform a flashing:

• install the program (corresponding to the car model) from the manufacturer;
• flash with a version of "unlicensed" software (associated with further risks);
• install the program of the control unit from the car, where the design does not provide for the presence of a particulate filter by default (it is possible to change the functional characteristics).

The flashing method consists of several stages. First, computer diagnostics are carried out to identify software errors. Establish the actual cause of malfunctions in the control unit system. Having diagnosed a malfunction in the particulate filter, the software is flashed. You can "get" to the file of the electronic control unit through the OBD connector or by removing the electronic BDM chip. Correction of the program file will affect the performance of the car:

• the engine speed will increase in driving mode, above 3000 per minute;
• the display error on the control panel is eliminated.

Changes to the firmware are approached with special attention, since it may be reflected in the vehicle's performance (associated with the electronic control unit). After the computer has erased the system errors of the software, they begin to mechanically remove the element.

Physical removal

The process involves removing the filter can located between the muffler and the exhaust manifold. Craftsmen dismantle the exhaust system and cut out a section with a particulate filter, replacing it with a pipe with a flame arrester or welding a plug. The method with a flame arrester is more relevant - the presence of sensors in the design allows you to avoid ECU errors. The work is performed within 2 to 6 hours - depending on the design features of the car model.

Installing a particulate filter emulator

"Deception", in the form of a particulate filter emulator, is installed to be able to reflash the control unit without changes in the operation of the systems. The emulator "shows" to the program controllers the presence of a filter in the exhaust system.

This "imitation of the presence" of the particulate filter will not affect fuel consumption. The installed software in the control unit forcibly starts the FAP regeneration mode.

The method is based on the installation of a snag with sensors. Signals sent to the controllers force the control unit program to function in standard mode.

Replacing a clogged SF is more profitable from an economic point of view. A new original filter costs decent money. Mechanical removal or installation of the emulator will save money, but it has its own characteristics that affect the operation of the car.

Positive consequences

Eliminate the need for unplanned long trips to clean the filter. Advantages are also observed in the operation of the control unit:

• eliminates software errors about the state of the particulate filter in emergency mode, on the instrument panel;
• oil consumption will be reduced by disabling regeneration.

Removing a faulty filter will have a positive effect on vehicle dynamics and traction. The engine will continue to operate in a stable and correct manner, the condition of the exhaust gases will change and the amount of smoke will decrease.

Negative consequences

Negative factors will manifest themselves during long trips in traffic jams and refueling a car with low-quality fuel. The permissible levels of exhaust gas emissions will exceed the established environmental standards, which will complicate the passage of technical control. A new vehicle may void warranty coverage (if the particulate filter is removed). Trucks may be banned from entering European countries, where environmental standards for emissions into the environment are closely monitored. The operation and movement of the vehicle is possible with the EURO-5 indicators.

Different types of fuels used in gasoline and diesel engines, as well as the fundamental difference in the methods of ignition of the combustible mixture in the cylinders, require designers to approach the problem of exhaust gas treatment differently.
The tightening of requirements for the content of harmful substances in exhaust gases also affected the norms that establish the maximum amount of solid particles they contain. In this regard, it was required to equip the exhaust system of diesel engines with a particulate filter, or, as it is commonly called, a particulate filter.
Let's figure out what it is - a diesel particulate filter, what features the operation of a car has, the exhaust system of which is equipped with a particulate filter.

Diesel particulate filter operation diagram

The particulate filter is designed to trap solid particles (soot) in diesel exhaust gases.

This element of the exhaust system is designed to trap solid particles (soot) contained in the exhaust gases of a diesel engine.
Accordingly, it is installed in the exhaust tract - moreover, depending on the design features of the car and the filter itself, it can stand immediately after the intake pipe or after the catalyst. Some designs combine a diesel particulate filter and a catalytic converter, the elements of which are located in a single housing.

How does a diesel particulate filter work?

Exhaust gases enter the closed channels and diffuse through their walls, entering the open channels. Further, the gases continue to move through the exhaust system, already cleaned of soot particles and, depending on the design of the exhaust system, enter either the catalyst or the muffler.
In cross-section, the DPF channels usually resemble regular octagons - this is the shape that maximizes the soot retention of the filter. The filter element is made of silicon carbide and is enclosed in a metal housing that does not resemble the rest of the exhaust system in shape. It is impossible to retain soot in another way due to the small size of its particles - about 0.05 microns.

Car operation with a particulate filter

Soot-clogged filter element

What is a diesel particulate filter on a car from the point of view of a driver who wants to get the most out of the engine?
This is, first of all, an obstacle in the way of exhaust gases - especially when it is clogged with soot. There are three ways to eliminate this interference or reduce resistance:

The particulate filter is an obstacle to the exhaust gas path - especially when it is clogged with soot.

• cleaning the particulate filter;
• its replacement;
• removing the filter altogether.

The service life of a diesel particulate filter is on average about 150,000 - 180,000 km. If the car is not used intensively, then this is a fairly large mileage, and you can replace the filter without resorting to additional actions - flashing the engine ECU, for example. But in the event that the car is working hard, and such a distance "covers" in two or three months, then it is preferable to completely exclude this element from the exhaust system - the prices for particulate filters installed on a diesel engine start at 900 euros, and engine oil for a diesel engine with a particulate filter, a special one is provided for and it costs more than the "usual" one.

Automatic cleaning of the diesel particulate filter

To control self-cleaning systems and (or) to signal to the driver that the filter is clogged with soot, sensors are mounted in its housing. In the event of a violation of the filter capacity, the DPF (Diesel Particulate Filter) lamp on the instrument panel will light up.
In addition, if the diesel particulate filter is clogged, the following symptoms appear:

• the power and traction of the engine decreases;
• fuel consumption increases;
• idle speed starts to "float".

An experienced driver will also notice a change in the sound of the engine.

Modern diesel engines are equipped with electronics that can enable a self-cleaning filter. Typically, self-cleaning is done in one of two ways:

Modern diesel vehicles are equipped with electronics that can enable the diesel particulate filter to self-clean.

1. The engine ECU, having processed the signal from the sensor installed in the particulate filter, gives a corresponding signal (Exhaust Gas Recirculation), which connects the exhaust and intake tracts, passing through part of the exhaust gases back into the cylinders. By changing the position of the valve flap, the EGR system forms the air flow in such a way that the gases entering the particulate filter are at a temperature higher than usual, and the soot is burned out.
2. Some cars are equipped with an additional container, which contains a special composition, when it gets into the particulate filter, contamination also burns out. The whole process is also controlled by electronics.

How to clean a diesel particulate filter yourself?

The particulate filter is clogged, as a rule, from insufficient heating of its filler, which leads to poor burnout of contaminants. This usually happens in urban driving conditions - when insufficient engine speed does not favor the heating of the exhaust tract. In addition, when the engine is idling or at low speeds, a rich fuel mixture enters the cylinders, which does not completely burn out.
If the design of the car provides only for informing the driver that the filter is clogged, then it is necessary to ensure the operation of the engine at high speeds - in order to raise the temperature of the "exhaust". Simply put - you need to "ride with the breeze."
You can also rinse the particulate filter with a special solution, having previously removed it from the car. For proper flushing, the entire filter housing should be filled. However, detailed instructions for using the flushing agent are usually printed directly on the label and do not provide for the use of any additional devices.

How to remove a diesel particulate filter

Particulate filter housing without filter element

Depending on the design features, the filter can be removed in the following ways:

Often, car owners simply remove the particulate filter, since replacing it is very expensive.

1. Remove the filter filler without disassembling its body - simply crushing it with any suitable tool. The catalyst, for example, is sometimes "knocked out" with a crowbar.
2. Open the body and weld it after "cleaning".
3. To make an insert from a suitable pipe - but this will require adjusting the flanges, which is more difficult than the previous two methods.

The most difficult thing in this procedure may be the subsequent "flashing" of the ECU - without changing the program, malfunctions in the engine operation after removing the filter are inevitable.
The consequences of removing the diesel particulate filter are:

• reducing the consumption of diesel fuel;
• improved dynamics of acceleration and engine thrust;
• reducing the cost of car maintenance;
• possible fines, especially outside the Russian Federation.

In conclusion, we can say that environmentalists have taken up the problem of excess soot "from the wrong end." The additional costs associated with the maintenance of diesel units equipped with particulate filters fell on the shoulders of ordinary motorists. Although it would be more correct to achieve the production of higher quality fuel without raising its cost. This is especially true for domestic oil refiners. More than 15 years ago, employees of one of the French laboratories, after analyzing Russian diesel fuel, concluded that this liquid is not diesel fuel at all.

Severe contamination of the particulate filter negatively affects the performance of the entire vehicle, and which car owner likes that the car has a noticeable increase in fuel consumption, decreased traction, and besides, annoying control lamps are on all the time. Of course, the issue can be resolved by replacing the part, but for this it will be necessary to pay a pretty decent amount. The only reasonable way out in this situation, from the point of view of most motorists, is to completely remove the filter from the car, but not everyone thinks about the possible consequences. More on this later in the article.

The diesel particulate filter is an essential element in the exhaust system of a diesel engine. The purpose of this device is to clean the exhaust gases from soot to prevent them from entering the environment (about 90 percent does not pass out).

The use of particulate filters began in 2001 on trucks. However, after the introduction of the Euro-5 environmental standard in 2009, all car manufacturers were obliged to install this filter element on cars of any type and class running on diesel.

The particulate filter is a metal cylinder. The cylinder has an outlet and an inlet branch pipes for connection to a common exhaust gas cleaning system. Inside it is a ceramic matrix. In addition to her, sensors are mounted on the particulate filter that monitor its operation. The DPF can be installed in different ways depending on the design.

How the particulate filter works

The particulate filter functions in two stages:

Stage 1 - the capture of soot. At this stage, soot particles settle on the walls of the filter element, which resemble cells in appearance. At the same time, soot does not remain completely here, but only particles larger than 0.5 microns in size. The rest comes out with exhaust gases, although the percentage of such precipitation is small - about 10 percent.

Stage 2 - regeneration. A laborious procedure for cleansing cells from soot deposits. The process takes place in accordance with the regulations prescribed by the manufacturer.

Methods for cleaning the particulate filter

There are two ways to clean the particulate filter - active (forced) and passive.

Passive regeneration is carried out by the car owner independently when the corresponding indication appears and with noticeable symptoms of deterioration in the operation of the power unit (decrease in dynamics, drop in power, and so on).

The most important thing in this case is to ensure an increase in the temperature for the exhaust gases, which can be obtained if you drive thirty to forty kilometers at full load. This driving mode ensures the combustion of soot and its cleaning. Alternatively, you can still use special additives in the fuel, which lead to a decrease in the combustion temperature of soot.

Active regeneration. Such a mode, which allows cleaning, can automatically turn on the motor control controller, for which it analyzes the information transmitted by the current temperature sensor and the differential pressure sensor. This sensor indicates that the particulate filter is clogged with soot particles, and the current temperature sensor determines its value. If the temperature is not enough for the soot to burn, the controller can, for example, perform an additional injection of fuel, produced when exhaust gases are discharged, which will entail its combustion directly in the exhaust system, and also increase the temperature of the exhaust gases to the required value.

If the exhaust system installed on a diesel engine provides for other measures aimed at increasing the temperature of the exhaust gases that enter the particulate filter, the control controller also activates them.

How a particulate filter differs from a catalyst

The DPF is designed to prevent / minimize the release of soot into the environment. It is considered part of the muffler and its main task is to clean the exhaust gases. But, you should not compare this device with a catalytic converter, since the catalyst fights with exhaust gases, and the particulate filter - only with soot in them.

Positive aspects of operating a diesel engine with a particulate filter

The positive aspects of the operation of a diesel engine with a particulate filter include the compliance of the car with environmental standards "Euro-5". The vehicle does not pollute the atmosphere, and people no longer have to breathe soot.

Negative aspects of operating a diesel engine with a particulate filter

There are a number of negative factors that arise when using a particulate filter:

1. Increased fuel consumption.
2. Substantial maintenance and replacement costs.
3. Loss of personal time due to the start of the regeneration (if it has started, it cannot be interrupted) and the maintenance of the car.
4. Systematic deterioration of vehicle performance as a result of reduced filter flow properties.

If the particulate filter is taken out of service, the positive and negative points

Benefits of removing a particulate filter:

• There is no need to service the filter element.
• The power unit is more stable.
• Improving the dynamic performance of the vehicle (increasing power).
• Reduced fuel consumption.
• There is no need for a regeneration mode.
• The absence of an emergency mode of the motor and errors due to a clogged filter.

Disadvantages of removing a particulate filter:

• Deteriorating environmental performance. Although it is possible to pass a MOT, the level of soot emissions into the environment increases dramatically.
• The vehicle is void of the warranty (if any).
• An increase in the load on the turbine, which slightly reduces its resource.
• In some cases, there is an increase in the amount of black smoke from the exhaust pipe.
• Problems with the operation of the car in the countries of the European Union, where all cars must comply with the environmental standards "Euro-5".

Steps for removing the particulate filter

The DPF removal process consists of two steps - physical and software.

physical stage of removal (step by step)

The physical stage is not difficult. Craftsmen find the jar containing the catalyst and filter and cut it out. On some car models, this will require removal of the exhaust pipe. Instead of the filter, you need to put something, for example, ordinary metal plugs or flame arresters. Installing a flame arrester will slightly increase the life of the muffler. If the element is equipped with carbon dioxide probes and temperature sensors, they may need to be removed and installed in a plug, which makes it possible to avoid programming errors.

1. First, we disconnect the sensors and cut the exhaust pipe located after the filter with a grinder.
2. Then we unscrew the bolts from the motor side, cut and open the filter casing.
3. We take out the device itself. Individual segments may need to be punched out.
4. We weld the case and install it in place. We connect the sensors.

reprogramming the engine block (methods of flashing)

After that, the power unit should be reprogrammed. If this is not done, the sensors will assume that the filter is permanently clogged. The result is a demonstration of fault codes, and sometimes the emergency mode is turned on altogether.

This part of the procedure is carried out only by the experts of the service center. The result can be achieved in three ways:

• Install the firmware from the vehicle manufacturer. This is the best option and carries virtually no risk.
• Install the firmware developed by enthusiasts. This is a kind of lottery - not the fact that you are lucky. The quality of the firmware varies greatly.
• Install the firmware from a version of the car, where by default there is no particulate filter. The method is fraught with a decrease in functionality, for example, on a Honda CRV, the cruise control is turned off.

In some Ford, Mazda, Toyota and Nissan models, it is impossible to perform a regular flashing - you have to use the emulation method. A dummy device is mounted, which makes the unit assume that the filter is in place. The controller does not notice the removal of the element, since it receives the corresponding signals. But this option has one drawback - the regeneration mode will turn on smoothly, so that the fuel consumption will not decrease.

Possible risks to which the car is exposed when carrying out the above works

Firstly, if you remove the particulate filter yourself, there is a risk of breaking something, which will entail even greater problems, and the cost of repairs will increase significantly.

Secondly, if the engine block is incorrectly reprogrammed, the system will see that the filter is not clogged, and this simply cannot be, so it decides that the particulate filter is faulty and puts the vehicle into emergency mode, not to mention the fact that the system will constantly give out trouble codes.

Thirdly, many motorists say that after removing this device, the dynamics of the car improves. The reason is obvious - as a result of the removal of the particulate filter, the resistance of the exhaust gases is reduced. However, is it good? Due to the increase in the flow rate of the exhaust gases, the rotation speed of the turbine increases, which, in this case, exceeds the design speed. As practice shows, often after removing the particulate filter, the turbine fails.

Do you need to remove the particulate filter? It's up to you to decide. The car really becomes simpler and cheaper to operate, power increases slightly. But you need to order this event only from highly qualified specialists, otherwise you can get more trouble than good.

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When a diesel engine is running, as a rule, there is no complete combustion of the fuel. As a result, together with the exhaust (exhaust) gases, components harmful to humans and the environment, including soot, enter the atmosphere. To reduce the concentration of the latter, a particulate filter is used. In English. option - Diesel Particulate Filter (DPF).

Design and arrangement in the system

The particulate filter belongs to the exhaust system and can be located next to or combined with it into a single structure (in this case, it is located near the exhaust manifold, which ensures gas filtration at maximum temperature). The device is used only in cars running on diesel fuel, and, unlike the catalyst, which is installed on gasoline engines, it cleans the exhaust exclusively from soot particles.

Particulate filter

Structurally, the particulate filter consists of the following elements:

• Matrix. It is made of silicon carbide (ceramics) and is a system of thin channels with a square or octagonal section. The ends of the passages are alternately closed, and the walls have a porous structure, due to which the soot is retained inside and settles on the walls.
• Frame. Made of metal. Has an input and output channel.
• Pressure measurement sensors (differential inlet and outlet).
• Inlet and outlet temperature sensor.

Features of the work and operation of the particulate filter

Passing through the particulate filter, impurities settle on the walls of the matrix, as a result of which purified gases are formed at the outlet. Gradually, the filter cells fill and clog, obstructing the passage of exhaust gases. This leads to a decrease in engine power, which indicates the need for cleaning or replacement.

The service life of the particulate filter depends on the operating conditions of the vehicle. On average, manufacturers recommend performing a condition check every 100,000 kilometers. The real range of filter contamination is from 50 to 200 thousand kilometers. To extend the service life, it is necessary to regularly regenerate and change the engine oil in a timely manner.

Types and tasks of regeneration

Diesel particulate filter regeneration is a procedure for burning soot that settles in the matrix. There are two types of regeneration:

• Passive - carried out by increasing the temperature of the exhaust gases. This can be realized by accelerating the engine to maximum load (about 15 minutes of driving at 3000 rpm or more) or by adding additives to diesel fuel that reduce the combustion temperature of soot.
• Active - performed when the main mode of engine operation does not provide the required parameters for passive regeneration. For this, a forced increase in temperature is performed for a while. The temperature rise is achieved in various ways - due to late or additional injection at the exhaust stroke, an electric heater or additional fuel additives.

Frequent piercing will wear out the ceramic matrix and lead to its destruction. And since the cost of a particulate filter is quite high, it is necessary to find the most gentle mode. It is achieved by increasing the amount of distance traveled between regeneration procedures, as well as reducing the temperature ranges of oil combustion.

The choice of oil for diesel

Unsuitable oil provokes additional contamination of the filter matrix cells and pre-wear. When the engine is running, it burns along with the fuel and, in the presence of incombustible sediment, blocks the operation of the exhaust gas cleaning system.

For diesel engines with particulate filters, ACEA (the Association of European Automobile Manufacturers) has established a certain oil standard that meets environmental standards not lower than Euro-4 and the rules for operating cars in general. Engine oils for modern diesel particulate filters that have ACEA approval have received the C mark (C1, C2, C3, C4). They are used for vehicles with exhaust cleaning systems, and their composition allows to extend the life of the matrix.

Is it possible to remove the particulate filter

Many motorists, wanting to get rid of the problem of constant cleaning and replacement and the additional financial costs associated with them, decide to remove the particulate filter. This can be done in several ways:

• Dismantling the device. Mechanical removal of the particulate filter allows for a slight increase in vehicle performance. On the other hand, when the machine is in operation, the engine ECU will start to generate an error, perceiving the lack of a filter as a malfunction.
• Making adjustments to the engine ECU software (updating the program to a version that does not contain information on connecting the particulate filter). Updating the software is carried out by a special device - a programmer, but at the same time it is necessary to be sure that the new firmware works correctly, since the consequences can be unpredictable.
• Connecting a device emulator (without changing the factory program), which sends signals to the ECU similar to the operation of a real particulate filter.

However, it should be borne in mind that the currently established environmental standards Euro-5 prohibit the operation of a car with a diesel engine without a particulate filter.