OA21437A - Process for descaling a heat engine by hydrogen injection and descaling station for its implementation. - Google Patents

Abstract

A descaling method is disclosed involving a diagnostic tool (10) of the engine (31) of a motor vehicle (30), which can interact with the engine control electronics (32) not only for reading information and control of certain organs during a cleaning procedure by hydrogen injection, but which can also check in real time, after cleaning, the state of the impacted organs and update engine management parameters in consequently, in control electronics. Thus, the electronic management of the engine can take into account the return to normal (ie, to the initial values or to values close to said initial values) of the operating parameters of the engine which are sensitive to engine scaling, such as the mobility of the valve. EGR, valve lift, DPF clogging, injector needle mobility, etc.

Description

Description

Title of the invention: Process for descaling a heat engine by hydrogen injection and descaling station for its implementation.

[Technical area]

The present invention relates generally to techniques for depolluting internal combustion engines (or heat engines), and more particularly to a process for descaling a heat engine by injection of hydrogen as well as to a descaling station for its implementation.

The invention finds applications, in particular, in the maintenance of internal combustion engines used in motor vehicles of all kinds, in the land sector (personal and utility vehicles, road transport trucks, agricultural vehicles, military vehicles , construction machinery for public works or forestry work, etc.) but also in other areas such as the navy or aeronautics, or even in thermal engines for generators. The examples thus given are not limiting.

[State of the prior art]

The clogging of the internal combustion engines of motor vehicles is essentially due to current conditions of automobile traffic, namely: - journeys are of increasingly reduced length, due to changes in use cases vehicles by individuals and professionals;

- engine starts are becoming more and more frequent (particularly due to stop and start systems known as “Stop and Start” aimed at reducing overall consumption in urban environments);

- speed limits are becoming lower and lower, due to state desires to reduce road deaths;

- the quality of certain fuels sold in low-cost stores (“/ow cost”), increasingly often devoid of detergent additives for reasons of economy in order to lower the displayed price of the fuels sold;

- increasingly strict anti-pollution standards, which lead car manufacturers to configure the operation of engines in order to limit measurable emissions during administrative validation tests of new vehicle models;

- low-speed driving practices, increasingly generally adopted by drivers in order to save fuel, the cost of which represents an increasing share of household budgets.

Carbonaceous combustion residues (e.g., carbon) settle inside the engine, particularly in sensitive parts such as:

- the turbocharger (or turbo): the carbon prevents the supercharging fins from tilting;

- the air intake circuit: the carbon obstructs the air inlet into the cylinder, which causes additional effort on the engine;

- the valves: once the carbon is installed, the valve seat is no longer 100% tight and this can affect the compression of the cylinder;

- the EGR system (from the English “Exhaust Gas Recirculation” which means recirculation of burnt gases): the exhaust gases carry these combustion residues and deposit them inside the EGR valve; an accumulation of scale impairs its movement;

- the head of the injectors: the scale prevents proper diffusion of the fuel during injection;

- the catalyst: the scale obstructs its cells;

- the particle filter (FAP): the scale causes it to clog; - etc.

The descaling of an internal combustion engine aims to combat the accumulation in the engine of these carbon residues, or soot, which is responsible for their clogging over time. These residues weaken the aforementioned engine parts, in particular, and cause harmful effects on engine performance and on the emission of harmful materials or particles into the environment.

In the past, each user has been able to rely, to a certain extent and with varying degrees of success, on the detergents contained in high-end fuel, or even on so-called descaling additives, to keep their engine clean.

In recent years, the descaling of an engine by hydrogen injection has appeared and offers an effective and inexpensive alternative in view of the benefits that can be expected. This process consists of injecting hydrogen inside the engine of a vehicle into the engine intake, while operating it at low speed, with the vehicle stationary, for a period of between thirty minutes and one about an hour and a half. This has the effect of removing soot deposits from inside the engine, this soot then being burned and/or released into the exhaust. The vehicle, once freed from the combustion residues which pollute its engine, substantially regains all the performances given by the manufacturer for a vehicle equipped with a new engine, and in particular sees a reduction in its fuel consumption.

Document FR3041997A discloses a descaling system comprising a control means arranged to control an opening or closing of the EGR valve of the engine as a function of parameters of the injected cleaning fluid, in order to better circulate the cleaning fluid in the upper engine part, in the intake circuit, and in the gas recirculation circuit. This control of the EGR valve which opens and closes during treatment allows it to be well cleaned.

Document FR3064025 discloses a cleaning installation comprising diagnostic means adapted to determine a clogging rate of a motor system comprising an internal combustion engine as a function of intrinsic parameters of said motor system, and means for controlling a device for injecting a fluid for cleaning the motorization system adapted to provide said injection device with cleaning parameters depending on the level of clogging of the motorization system. Thus, the fluid injection is adjusted taking into account a clogging rate of the engine system depending on intrinsic parameters of the engine system, such as for example the geometry of the engine, the number and diameter of the cylinders, etc. , for better cleaning efficiency.

In the cleaning installation according to document FR3064026, moreover, a diagnostic means is arranged to determine a rate of clogging of the motor system as a function of a rate of defect of at least one of the moving parts, and a control means arranged to provide the injection device with cleaning parameters for implementing the cleaning sequence, said cleaning parameters being a function of the level of clogging of the motorization system. Thus, the injection of cleaning fluid is adjusted taking into account a rate of clogging of the motor system depending on a rate of defect of at least one moving part. The cleaning sequence is thus adapted to the actual needs of the engine, and not based solely on a statistical state of engine fouling.

The state of the art summarized above reveals that the general principle of descaling an internal combustion engine by injection of hydrogen is the subject of continuous improvements, resulting essentially from interaction with the vehicle specifically concerned by the 'operation in progress.

However, it appears that this interaction with said vehicle, even if it makes it possible to take into account the state of the vehicle just before carrying out the operation, can still be improved.

In particular, all internal combustion engines in modern vehicles are managed electronically, by one (or more) on-board management unit(s). These management units each include at least one computer which controls the operation of the engine according to various parameters such as engine speed (idling, acceleration, etc.), engine load (full load, engine braking, etc.), the acceleration request (deceleration, recovery), the engine temperature, the operating phase (cold start, urban journey with frequent stops and starts if a “Stop and Start” function is implemented, etc.), and even more. Thanks to this technology, all factors of good operation are taken into account to adjust certain engine control parameters such as injection duration, pre-injection timing, injection and post-injection, etc.

Engine fouling, which is one of the parameters associated with the aging of engine parts, is also taken into account by these electronic engine management units, as a slowly changing parameter.

However, injecting hydrogen in order to eliminate or reduce the carbon inside the engine during a descaling operation has the effect that the electronic management of the engine is suddenly no longer in phase with the actual condition of the parts which are particularly subject to scaling. These parts are in fact, from the point of view of the electronic engine management units, considered to be intrinsically dirty with the effect of reducing the efficiency of their operation compared to what it was when the engine was put into service. And yet these parts suddenly find themselves partially or totally regenerated due to the descaling operation which has just been carried out. For this reason, the parameters taken into account by the electronic engine management units which are linked to clogging (valve lift height, injector opening rate, DPF clogging rate, etc.) become at least partially erroneous since the effects of aging attributed to the progressive formation of carbon in the engine disappear in whole or in part due to the descaling operation carried out.

[Disclosure of the invention]

The invention aims to improve the situation and proposes for this purpose, in essence, to inform all of the electronic management units of the engine of the completion of a descaling operation. Thus, the electronic management of the engine can take into account the return to normal (i.e., to the initial values or to values close to said initial values) of the operating parameters of the engine which are sensitive to engine scaling, such as the mobility of the valve EGR, valve lift, DPF clogging, injector needle mobility, etc.

This goal is achieved thanks to a cleaning method involving a diagnostic tool for the power unit, which can interact with the engine control electronics not only for reading information and controlling certain components during the cleaning procedure. , but which can also check in real time the state of the components affected by cleaning and update engine management parameters accordingly in the control electronics of the powertrain.

More specifically, a method is proposed for cleaning a motor vehicle power unit comprising an internal combustion engine, said method comprising:

- the reading, by a diagnostic tool connected to the motor vehicle, of faults in the motorization group possibly indicated by electronic control of the motorization group during the previous operation of the motorization group and stored, where appropriate, in a memory of said control electronics;

- reading by the diagnostic tool in real time, with the engine running, of operating parameters of the power unit, and establishing a diagnosis relating to the clogging of components of the power unit based on the faults reported , if applicable, as well as said operating parameters of the motorization group;

- the connection to the vehicle of a cleaning station of the power unit by injection of a cleaning fluid, said cleaning station being further connected;

- under the control of the diagnostic tool and according to a cleaning procedure which depends on the established diagnosis, cleaning of the power unit by injection, with the engine running, of a cleaning fluid in the engine intake by a cleaning station connected to the motor vehicle and connected to the diagnostic tool for the purpose of its control by said diagnostic tool, with simultaneous setting in motion, also under the control of the diagnostic tool, of mobile members of the powertrain group included among the organs of said motorization group which are sensitive to clogging;

- the erasure by the diagnostic tool of the faults reported, if applicable, from the memory of the power unit control electronics;

- learning, after the cleaning operation, by the diagnostic tool, in real time, with the engine running, the actual state of self-adaptive components of the motorization group included among the organs of said motorization group which are sensitive to clogging; And,

- updating by the diagnostic tool, in the control electronics of the motorization group, of operating parameters of said motorization group normally influenced by the fouling of organs of said motorization group which are sensitive to the clogging, to take into account the actual state, after the cleaning operation, of the self-adaptive organs of the motorization group among the organs of said motorization group which are sensitive to fouling.

Implementation methods, taken individually or in combination, also provide that:

- cleaning of the engine can be carried out for a period of time which also depends on intrinsic parameters of the power unit, such as the displacement of the engine;

- the components of the power unit which are sensitive to clogging include in particular the turbo, the particle filter, the EGR valve, the Bypass box, the valves, the exhaust valve, and the injectors;

- the moving parts of the engine group among the parts of said engine group which are sensitive to clogging include in particular the turbo, the exhaust valve, the EGR valve, the valves and the injectors;

- the self-adaptive components of the powertrain group among the components of said powertrain group which are sensitive to clogging include in particular the EGR valve, the exhaust valve and the valves;

- the diagnostic tool can be a connected tablet, associated with the cleaning station;

- the diagnostic tool can be connected to the control electronics of the power unit via the vehicle's OBD socket;

- the cleaning station can be functionally connected to the diagnostic tool via a USB link, a Bluetooth™ link, or a Wi-Fi™ link; and/or - the cleaning fluid may be hydrogen.

In a second aspect, the invention also relates to a diagnostic tool adapted to be functionally connected to a cleaning station, by injection of a cleaning fluid, of a motor vehicle power unit comprising an internal combustion engine , said diagnostic tool comprising means for implementing all the steps of the method according to the first aspect above.

[0001] A third aspect of the invention relates to an installation for cleaning a motor vehicle power unit comprising an internal combustion engine, said installation comprising a cleaning station adapted for injecting a cleaning fluid into the motorization group, engine running, and a diagnostic tool according to the second aspect above adapted to be functionally connected to a cleaning station in order to implement the method according to the first aspect.

In a fourth and final aspect, the invention also relates to a computer program product comprising one or more instruction sequences stored on a machine-readable memory medium comprising a processor, said instruction sequences being adapted for carry out all the steps of the method according to the first aspect of the invention when the program is read from the memory medium and executed by the processor.

We can note a reduction of 10 to 38% in consumption for a depolluted vehicle thanks to the implementation of the invention. The proposed system, in view of such numerical elements, demonstrates its effectiveness, both in terms of energy saving, as well as in terms of respect for the environment and consideration of public health issues linked to quality. air.

[Description of the designs]

Other characteristics and advantages of the invention will become apparent on reading the description which follows. This is purely illustrative and must be read in conjunction with the appended drawings in which:

[Fig. 1] Figure 1 is a functional diagram schematically illustrating an installation for cleaning a power unit of a motor vehicle comprising an internal combustion engine, with a diagnostic tool and a descaling station, in which modes of carrying out the invention can be implemented; And,

[Fig. 2] Figure 2 is a step diagram illustrating the implementation of the method of the invention.

[Description of embodiments]

In the description of embodiments which follows and in the Figures of the appended drawings, the same or similar elements bear the same numerical references to the drawings.

An internal combustion engine releases, during operation, harmful gases and products such as;

- carbon dioxide (CO2) responsible for warming the atmosphere;

- carbon monoxide (CO) which is partly responsible for the progression of cardiovascular diseases;

- unburned hydrocarbons (HC) which are carcinogenic; And,

- nitrogen monoxide and dioxide (generally called NOx) in the form of fine particles that are highly harmful to the human pulmonary system.

Despite the efforts made to reduce these emissions, in particular by reducing fuel consumption by thermal engines but also by implementing depollution techniques, the impact of human activities involving the use of thermal engines remains worrying for the planet and for humanity.

Descaling is a process for cleaning engine groups comprising an internal combustion engine, which contributes to reducing emissions of the aforementioned polluting products, by combating the accumulation of carbonaceous soot in the organs concerned, which is responsible for the reduction in vehicle performance and the increase in pollutants with vehicle age.

Remember that the technique of descaling a thermal engine by hydrogen injection consists of injecting hydrogen inside the engine, while the engine is operating at low speed. This hydrogen is made solely from demineralized water. No chemicals are added. This is why, and although other cleaning fluids are possible, hydrogen is currently the most widespread. This is also why the embodiments considered here relate to cleaning a motor unit by hydrogen injection. Those skilled in the art will appreciate, however, that the implementation of the invention is not limited to this example.

Hydrogen injection allows in particular:

- reduce engine emissions of harmful particles into the atmosphere (CO, CO2, NOx and HC);

- reduce fuel consumption (a factor noted by the reduction in CO2 and HC emissions);

- improve engine performance (torque and power); and, - to clean and regenerate wearing parts such as the injectors, and where applicable the turbo, the EGR valve, the particle filter (FAP), etc., which reduces the risks of changing these expensive parts and therefore an indirect but substantial saving for the vehicle owner.

Figure 1 shows, very schematically, a functional diagram of a cleaning installation of an engine group 31 of a motor vehicle 30 comprising an internal combustion engine, with a diagnostic tool 10 and a descaling station 20, in which embodiments of the invention can be implemented. As will become more apparent to those skilled in the art in light of the description which will be given in the following, the steps of the method are more particularly carried out by, or under the direct control of the diagnostic tool. The operator's intervention can be limited to connecting the devices, and triggering the operation of the tool which then operates relatively automatically, in particular to control the cleaning station 20 and to read/write access to the electronic control 32 of the motorization group 31 of the motor vehicle 30.

In one embodiment, the diagnostic tool can be a connected tablet, associated with the cleaning station 20, or a functionally equivalent device such as a mobile phone (or “smartphone”) or a laptop computer (or “laptop computer”). ), equipped with software and an interface for communicating with the on-board computers of the control electronics 32. Alternatively, it may be a market diagnostic case equipped with software for the vehicles of the main brands (also called “multi-brand suitcase”), or a general-purpose computer (“desktop computer”) equipped in the same way, and equipped with an interface to communicate with the on-board computers.

Note that, in all embodiments, the diagnostic tool is sold without any software and any data file corresponding to cleaning procedures. The user of the cleaning station can apply exclusive procedures, which he will have developed closely with the cleaning station he uses in connection with the connected diagnostic tool.

He can also install in the diagnostic tool 10 the diagnostic software 110 corresponding to the different types of motor vehicles supported in his workshop (light passenger vehicles, utility vehicles and heavy goods vehicles, agricultural vehicles, construction machinery, boats and ships). , diesel-powered railway tractors, aircraft, etc.), and where applicable a customer file 120 which seems most suitable.

For example, the diagnostic tool 10 can be connected to the control electronics 32 of the motorization group 31 via the OBD socket, referenced 34, of the vehicle 30, via an interface cable 14. The standard OBD is the only standard for all car manufacturers. It is the standard for on-board diagnostic systems (OBD from English “OnBoard Diagnostic”) which is intended to enable the control of polluting emissions by being able to detect the probable origin of a malfunction by means of diagnostic codes. error stored in the computer's memory, particularly during technical inspection sessions. According to the specifications of this standard applicable in Europe, in addition, when a major OBD fault code is detected, the computer turns on the engine pollution warning light on the dashboard. Alternatively, the functional connection between the tool 10 and the control electronics 32 can also take place by other means, wired or wireless.

By the expression connected tablet “associated” with the cleaning station 20, we mean that it can be supplied with said cleaning station, by the manufacturer of the latter. But it can also be a digital tablet on the market, intelligent and communicating, in which an application can be executed which implements the method and which includes means of operational connection, wired or wireless, with the station cleaning 20. In summary, the diagnostic tool 10 can be connected to the cleaning station 20 via a wired connection 23,13 such as a USB™ connection established by a USB™ cable 23 of the station with a USB™ socket 23 of the tool 10, for example a USB-3™ connection, or by a wireless connection for example a Bluetooth™ connection or a Wi-Fi™ connection.

The cleaning station 20 further comprises a pipe 21 for delivering the cleaning fluid, here hydrogen, to the power unit 31 of the motor vehicle 30, via a. ad-hoc means of connection to the vehicle. More particularly, hydrogen is injected into the engine intake, for example via the air intake manifold (or pipe). This can take place downstream of the air filter, for a spark ignition vehicle (or so-called “petrol” vehicle), or downstream of the EGR valve for a Diesel vehicle.

Finally, Figure 1 shows that the diagnostic tool 10 can also include means of connectivity, such as another USB™ socket 11, to be connected by a USB™ cable 41, to a peripheral 40 such as a printer, which allows print diagnostic reports, advantageously before and after the cleaning carried out. Of course, any other connectivity interface, such as Bluetooth or Wi-Fi™ can be considered. Furthermore, the tool can also be adapted to connect to any other equipment in the workshop, such as a gas analyzer for example, for the analysis, simultaneous or not, of the quantity and composition of gases. exhaust, advantageously before and after the cleaning carried out.

With reference to the step diagram in Figure 2, we will now describe the implementation of the process for cleaning the power unit of the motor vehicle 30 in Figure 1.

First of all, it should be noted that a standard implementation of engine cleaning by hydrogen injection according to the prior art includes the following steps, implemented by an operator in a specialized workshop - reading of any defects ;

- the connection of the descaling station at the engine intake level, for example after the air filter for a spark ignition engine, or after the EGR valve for a Diesel engine;

- the injection of hydrogen according to the method recommended by the station manufacturer (in particular for a period of time according to indications provided by the station manufacturer);

- then stopping the hydrogen injection;

- reading and erasing engine faults; and finally - returning the vehicle to the customer.

In step 201 of the method according to modes of implementation of the invention illustrated by the step diagram of Figure 1, an operator connects the diagnostic tool 10 to the motor vehicle 30, for example via the OSB socket referenced 34 of said vehicle.

In step 202, the diagnostic tool 10 reads faults in the motorization group possibly indicated by the control electronics 32 of the motorization group comprising the internal combustion engine 31, during the previous operation of the motorization group . Such faults are conventionally stored, where appropriate, in a non-volatile memory of the control electronics 32, for example an EEPROM (Electrically Erasable and Programmable Read-only Memory) memory, or a Flash memory. .

Step 203 includes the reading by the diagnostic tool 10, in real time and with the engine running, of operating parameters of the motorization group. It also includes the establishment, still by the diagnostic tool 10, of a diagnosis relating to the clogging of components of the motorization group based on the faults reported, if applicable, as well as the operating parameters of the group of motorization read in the memory of the electronics 32. Those skilled in the art will appreciate that these are organs of the motorization group which are sensitive to clogging by carbon residues (scale), in particular the turbo , the particle filter, the EGR valve, the Bypass box, the exhaust valve, the valves controlled by the variable distribution system or WT (from the English “Variable Valve Timing”), and the injectors. This list is not exhaustive.

In step 204, the operator connects the cleaning station 20 to the vehicle 30, which is adapted to ensure the cleaning of the power unit by injection of a cleaning fluid, namely hydrogen into the example. The cleaning station 20 is further connected to the diagnostic tool 10 to operate under the control of said diagnostic tool, as part of the cleaning procedure established by this tool.

This cleaning procedure is for example established on the basis of standard procedures, one of which is selected and adapted (by configuring ad-hoc parameters, for example) according to the defects noted in step 202 and the diagnosis established in step 203, in particular.

In a first example, if defects are noted and/or if malfunctions are noted in the EGR system, the cleaning procedure may include: - heating the engine to 80°C;

- connect the hydrogen hose to the air duct located after the air filter;

- start the hydrogen injection once the engine is started;

- let the engine idle for 60 minutes while controlling the opening and closing of the gas recycling valve using the diagnostic software;

- then, for 30 minutes, vary the engine speed according to the operating range of the EGR valve;

- then accelerate the engine speed to 2300 rpm for 30 minutes; and finally, - stop the hydrogen injection then reconnect the air hose.

In a second example, if faults are noted and/or if malfunctions are noted at the level of the particle filter (FAP), the cleaning procedure may include: - recording the differential pressure value of the FAP;

- heat the engine to 80°C;

- connect the hydrogen hose into the air hose located after the air filter;

- start the hydrogen injection once the engine is started;

- let the engine idle for 60 minutes;

- increase the engine speed to 1800 rpm for 30 minutes;

- accelerate the speed to 2700 rpm for 30 minutes; then finally, - stop the hydrogen injection then reconnect the air hose.

In a third example, if defects are noted and/or if malfunctions are noted in the EGR system, the cleaning procedure may include: - heating the engine to 80°C;

- connect the hydrogen hose to the air duct located after the air filter;

- start the hydrogen injection once the engine is started;

- let the engine idle for 50 minutes;

- increase the engine speed to 1800 rpm for 30 minutes;

- vary the engine speed from entry to exit from the boost range for 30 minutes; and finally, - stop the hydrogen injection then reconnect the air hose.

Those skilled in the art will appreciate that these examples are in no way limiting.

The cleaning procedure can also, in general, provide that the cleaning of the engine will be carried out for a duration which depends, in addition, on intrinsic parameters of the engine group, such as the displacement of the engine, the age and/or the total mileage traveled by the vehicle since it was put into service, etc. Other more subjective parameters, such as the dominant type of use of the vehicle (short daily journeys in urban cycles, or on the contrary long occasional journeys on the motorway, for example) and entered directly by the operator in the diagnostic tool 10 (to the extent that they are known) or retrieved from the customer data file 120, for example, can also be taken into account to establish the cleaning procedure most suited to the particular case of the vehicle to be descaled.

In step 205, the diagnostic tool controls the cleaning of the power unit by injection, with the engine running, of the cleaning fluid in the engine intake, namely hydrogen in the example considered here. During this step, and at the same time as the hydrogen injection is carried out, the mobile members of the motorization group included among the members of said motorization group which are sensitive to clogging are preferably set in motion, according to modalities belonging to the cleaning procedure mentioned in the previous paragraph, which depends on the diagnosis established. For example, the moving members of the powertrain group among the members of said powertrain group which are sensitive to clogging include the turbo, the EGR valve, the exhaust valve, the valves and the injectors. This list is not exhaustive.

In step 206, the diagnostic tool commands the erasure of the faults reported before cleaning, if necessary, the memory of the control electronics 32 of the vehicle power unit 30.

In step 207, the diagnostic tool 10 further learns, after the cleaning operation, in real time and with the engine running, the actual state of the self-adaptive members of the motorization group which are included among the organs of said motorization group which are sensitive to clogging. For example, the self-adaptive components of the powertrain group among the components of said powertrain group which are sensitive to clogging include the EGR valve, the exhaust valve and the valves (through the WT system). This list is not exhaustive either.

Finally, in step 208, the diagnostic tool updates, in the control electronics 32 of the motorization group of the vehicle 10, the operating parameters of said motorization group which are normally influenced by fouling. organs which are sensitive to fouling. This advantageously makes it possible to take into account the actual state, after the cleaning operation, of the self-adaptive members of the motorization group among the members of said motorization group which are sensitive to clogging. In other words, the operation of the power unit after cleaning by hydrogen injection will take into account the return of said organs to a state identical to or close to their initial state, when the vehicle is put into service 10. Reduction of consumption and fuel and the emission of harmful products into the atmosphere are therefore optimized, as are the vehicle's performances.

Those skilled in the art will appreciate that the order of step 206, on the one hand, and of steps 207 and 208, on the other hand, is indifferent.

The present invention has been described and illustrated in the present detailed description and in the figures of the accompanying drawings, in possible embodiments. The present invention is not limited, however, to the embodiments presented. Other variants and embodiments can be deduced and implemented by those skilled in the art on reading this description and the accompanying drawings.

In the claims, the term comprising or comprising does not exclude other elements or other steps. A single processor or several other units can be used to implement the invention. The different characteristics presented and/or claimed can be advantageously combined. Their presence in the description or in different dependent claims does not exclude this possibility. The reference signs cannot be understood as limiting the scope of the invention.

Claims (12)

[Claim 1] Method for cleaning a motor vehicle power unit (30) comprising an internal combustion engine (31), said method comprising: - the reading (202) by a diagnostic tool connected to the motor vehicle (30), of faults in the motorization group possibly indicated by control electronics (32) of the motorization group during the previous operation of the motorization group and stored, where appropriate, in a memory of said control electronics; - reading (203) by the real-time diagnostic tool, with the engine running, of operating parameters of the motorization group, and establishing a diagnosis relating to the clogging of components of the motorization group in operation reported faults, if any, as well as said operating parameters of the motorization unit; - the connection (204) to the vehicle of a cleaning station (20) of the powertrain group by injection of a cleaning fluid, said cleaning station being further connected; - under the control of the diagnostic tool and according to a cleaning procedure which depends on the established diagnosis, cleaning (205) of the power unit by injection, with the engine running, of a cleaning fluid in the intake of the engine by a cleaning station connected to the motor vehicle and connected to the diagnostic tool for the purpose of its control by said diagnostic tool, with simultaneous setting in motion, also under the control of the diagnostic tool, of mobile members of the motorization group included among the organs of said motorization group which are sensitive to clogging,; - the erasure (206) by the diagnostic tool of the faults reported, if applicable, from the memory of the control electronics of the power unit; - learning (207), after the cleaning operation, by the diagnostic tool, in real time, with the engine running, the actual state of self-adaptive members of the motorization group included among the members of said group motorization which are sensitive to clogging; and, - updating (208) by the diagnostic tool, in the control electronics of the motorization group, of operating parameters of said motorization group normally influenced by the fouling of organs of said motorization group which are sensitive to fouling, to take into account the actual state, after the cleaning operation, of the self-adaptive members of the motorization group among the members of said motorization group which are sensitive to fouling. [Claim 2] Method according to claim 1, in which the cleaning of the engine is carried out for a duration which depends, in addition, on intrinsic parameters of the power unit, such as the displacement of the engine. [Claim 3] Method according to claim 1 or claim 2, in which the organs of the power unit which are sensitive to clogging include the turbo, the particle filter, the EGR valve, the Bypass box, the valves, the exhaust valve, and the injectors. [Claim 4] Method according to one of claim 3, in which the movable members of the motorization group among the members of said motorization group which are sensitive to clogging include the turbo, the exhaust valve, the EGR valve, valves and injectors. [Claim 5] Method according to claim 3 or claim 4, in which the self-adaptive members of the motorization group among the members of said motorization group which are sensitive to fouling include the EGR valve, the exhaust valve and the valves. [Claim 6] Method according to any one of claims 1 to 5, in which the diagnostic tool is a connected tablet, associated with the cleaning station. [Claim 7] Method according to any one of claims 1 to 6, in which the diagnostic tool (10) is connected to the control electronics of the power unit via the OBD socket (34) of the vehicle (30). [Claim 8] Method according to any one of claims 1 to 7, in which the cleaning station (20) is functionally connected to the diagnostic tool (10) via a USB™ link (23, 13), a Bluetooth™ connection, or a Wi-Fi™ connection. [Claim 9] Method according to any one of claims 1 to 8, wherein the cleaning fluid is hydrogen. [Claim 10] Diagnostic tool adapted to be functionally connected to a cleaning station, by injection of a cleaning fluid, of a motor vehicle power unit (30) comprising an internal combustion engine (31), said tool diagnostic instrument comprising means for implementing all the steps of the method according to any one of claims 1 to 9. [Claim 11] Installation for cleaning a motor vehicle power unit (30) comprising an internal combustion engine (31), said installation comprising a cleaning station adapted for injecting a cleaning fluid into the group of motorization, rotating engine, and a diagnostic tool according to claim 10 adapted to be functionally connected to a cleaning station in order to implement the method according to any one of claims 1 to 9. [Claim 12] Computer program product comprising one or more instruction sequences stored on a machine-readable memory medium comprising a processor, said instruction sequences being adapted to carry out all the steps of the method according to one any of claims 1 to 9 when the program is read from the memory medium and executed by the processor.