Methods of cleaning the injector

Modern fuel injection systems are based on the use of injectors. Under the modern injector should be understood as fuel injectors, which have a solenoid valve. The weak point of the injection system is that, that the injectors are gradually contaminated during operation. The injector is clogged with dirt even if it is, that the engine runs on good quality fuel. The use of low-grade gasoline naturally accelerates this negative process.

We also recommend reading the article on tuning the fuel system of the injector engine. This article presents the principle of operation of the injection system and considers its main elements.

Over time, chemical elements and various compounds (sulfur, benzene, olefins), contained in the fuel, turn into resinous deposits and hardened varnish. This is due to the high pressure in the injection system (from 2.5 up to 6 atm.) And the operation of the nozzles in high temperatures (80-100 ° C). Such formations are quite difficult to wash off.

The result of pollution is a noticeable deterioration of the engine-falling power, reduced susceptibility, there is instability of revolutions in the idle mode, fuel consumption increases. At intensive dispersal there are failures, and the toxicity of exhaust gases increases, which entails a significant reduction in the service life of the catalyst and lambda probe. The ECU becomes more difficult to adjust the fuel-air mixture in relation to different modes of operation of the engine. Clogged nozzles are not able to provide the required performance, the shape of the torch changes, direction of sawing, and complete cessation of fuel supply through the injector is possible.

Practice shows, that high-quality European gasoline eliminates the need for frequent cleaning of the injector. If the engine is operated on such fuel, then cleaning may be required once in 120-150 thousands of kilometers. If we talk about the CIS countries, then the injector system often needs to be cleaned already through 30-40 thousands of kilometers.

The most noticeable clogging of fuel injectors becomes with the advent of the cold season. At this time, the evaporation of fuel is reduced, problems with starting a cold engine begin to appear, as well as noticeable failures in its work in different modes, etc..

Methods of flushing the injector

There are several ways, which allow you to flush the injector. The choice of each method is determined by the degree of contamination of the fuel supply system, wear of the power plant itself and other factors.

Pour the rinse into the gas tank

The simplest and at the same time gentle way of cleaning is filling in a fuel tank of the car of special washing. Such a fuel system cleaner is usually sold in bottles of approx 300 ml. This amount is enough for 60-70 liters of fuel. The principle of action of the additive is, that in the process of driving it gradually dissolves deposits in the injection system and partially prevents their further formation. It is necessary to add cleaner to fuel regularly (each 4-5 thousand km. Mileage). If you are unsure, that you use fuel of proper quality, then it is recommended to reduce the specified interval.

It should be noted, that this method is only suitable for those cars, which are new or have a short service life in the CIS. In this case, washing in the tank is a "preventive" measure, which allows you to keep the injector and fuel system of the car clean.

For those cars, in which the fuel supply and injection system is already heavily contaminated, this method of cleaning is not suitable. Moreover, flushing in the fuel tank can even worsen existing problems. Washed by the cleaner dirt and deposits get into the nozzles and clog them even more. After that it will be necessary to dismantle and clean fuel injectors in other ways. The second aspect is the high probability of that, the dirt washed in the gas tank will clog the fuel pump. Contamination of the electric gasoline pump leads to its increased wear and reduced efficiency of the device.

Cleaning the injector without removing the injectors

The injector can be cleaned as follows, so as not to remove the injectors and fuel rail from the engine. A special flushing unit and cleaning fluids are used for cleaning. Wynn’s and Liqui Moly are the most widely used formulations.

The cleaning process is carried out by connecting the flushing unit through the adapters directly to the vehicle injector. This allows you to exclude from the chain of gas tanks, gasoline pump, fuel filter and fuel lines. With this approach, the dirt is washed away exclusively in the fuel rail and injectors. The car's engine is started and run on a mixture of gasoline and flushing fluid 30-40 minutes at idle. The mixture is fed from the washing unit at a pressure of 3 to 6 atmospheres. The pressure is regulated according to the technical requirements for the specific car model.

Cleaning process and results

Composition for cleaning, mixed with gasoline, actively softens and washes away contaminants accumulated in the injector. Then the installation pushes dirt through the injectors into the engine cylinders, where the washed away deposits finally burn. This method of washing is actively used in the case of moderate contamination, as well as for certain design difficulties (to remove the injectors it is necessary to dismantle the intake manifold or other attachments).

The quality of the injector cleaning procedure can be determined by the following features:

• stable operation of the internal combustion engine at idle speed;
• no failures in other modes of operation;
• increase in return from the motor;
• positive changes in acceleration dynamics and throttle response;
• reducing the content of harmful substances in the exhaust, etc. .;

For most cases, this method of cleaning the injector is sufficient to restore normal operation of the injector system. Cleaning the injector in this way should be done once in 30-50 thousand km. After rinsing without removing the injectors in the fuel rail and the injectors themselves, some liquid remains, that cleanses. Small remnants of flushing get into the engine oil. For this reason, it is recommended to drive first 20-30 km. in high speed mode to remove residue from the injector.

Pay attention again, that after cleaning on the car part of a liquid for washing will be found in oil system of the engine. The injector must be cleaned before replacing the engine oil and filters, and not after. Також рекомендується після промивання змінити і свічки запалювання.

In some cases, it may be necessary to replace the sealing rings of the injectors in the event of fuel leaks through them.. This effect is observed because, that the flushing fluid is more or less aggressive towards rubber seals. When comparing common Liqui Moly and Wynn’s washes, then, according to some reviews, the first option has a milder effect on rubber.

Warning! It is not recommended to clean heavily worn engines in this way. Together with intensive cleaning of the injector system from various deposits in such motors in parallel there is a removal of a deposit and deposits on piston rings and walls of cylinders of the engine.. This can in some cases lead to a significant loss of compression and the engine will not start after such flushing..

It is recommended not to clean the KE-Jetronik injector systems separately on the injector cleaning unit without removing them., where mechanical fuel injection takes place. Such systems received dispensers with small operating gaps, which makes them extremely sensitive to dirt and deposits. In the process of rinsing the dispensers are quickly clogged, which leads to the need to remove the injectors and further more complex repairs. In mechanical injection systems, the injectors are non-detachable, and their purification is carried out by the method of purging with compressed air. If the mechanical nozzle is very dirty, then a complete replacement of this element will be required.

Cleaning with removal of nozzles

Heavy contamination of the injection system is removed in this way, which implies the removal of nozzles and their separate cleaning. This method allows you to achieve the best results. The main advantage of cleaning injector nozzles with liquid is the restoration of such injectors, which structurally have a complex configuration of their internal channels.

The injector is dismantled and individual cleaning of each nozzle is performed on a special stand. This approach allows you to compare performance, torch shape, direction and quality of sawing before and after cleaning. Additionally, you can compare and analyze the work of the whole group of injectors together.

The principle of operation of the cleaning stand is, that its control system simulates the operation of the injectors on the engine. Instead of gasoline, injector flushing fluid is passed through them. The stand operator controls the frequency of electrical oscillations of the injector valve. The main task is the emergence of cavitation in the fuel supply channel. Cavitation should be understood as the formation of air bubbles in a liquid.

Hydrodynamic cavitation ensures the movement of the injector needle in the fluid flow, that cleans with great speed. A vacuum is formed on various convex parts. Under the pressure of the surrounding fluid, the vacuum is instantly divided into a large number of microscopic bubbles, "clapping". The effect of microexplosions is obtained, and the energy from them affects the varnish and mud deposits, formed inside the fuel channel of the injector and on the needle itself.

The result of this operation is the effective destruction and removal of deposits and dirt in the channels of the nozzle, as well as flushing the injector strainer. The resulting cavitation is determined by the operator visually. A stream of light liquid, coming out of the nozzle, turns brown. The color of the liquid at the outlet changes due to slag, exfoliating.

The stand allows to reveal in addition changes of parameters of work of electric and mechanical elements of nozzles. This allows you to decide in advance about the need to clean the injectors, expediency of their further use without washing or complete replacement.

The performance of the injectors is determined as before, and after their cleaning. In those cases, when the cleaned injectors show different performance indicators with overclocking of more than 5%, then they need to be replaced. Defective nozzles are replaced as one piece, and the group.

Flushing reveals that, that the solenoid valve is worn and does not close completely. This means, that such a nozzle is flowing at that moment, when no electrical impulse is applied to it. This fault leads to fuel consumption, the scale on the valves increases, violated, etc.. It is better to replace injectors with a similar problem at once.

Ultrasonic injector cleaning

One common way to clean nozzles is to use an installation, which cleans pre-removed injectors in a special ultrasonic bath. This method provides high results, although some experts believe that the best way to clean the nozzles is hydrodynamic cavitation.

The ultrasonic bath is an open container, which is filled with cleaning fluid. The device is mounted from the outside to the bottom of such a bath, which is an emitter of ultrasonic vibrations. The nozzle of the nozzle for cleaning is lowered into the bath. As it passes through the cleaning fluid, the ultrasonic wave starts the cavitation process. Bubbles form during cavitation, which burst and form shock waves. These waves have a destructive effect on dirt and deposits, which accumulate on the surface of the nozzle nozzle and in the channels.

Nozzle filter replacement

Decrease or absence of positive effect after cleaning of nozzles on the washing or ultrasonic stand can be caused by clogging of the strainer of thin cleaning. The specified basket filter is made of kapron and is installed in the inlet fitting of the injector.. This filter can be clogged with the smallest insoluble fractions and particles. Among them it is worth noting not only dirt, but also metal dust, which is formed and accumulates on the filter as a result of the gradual wear of the fuel pump parts.

Most nozzles of different types structurally allow you to replace the strainer with a new element. Replacement is made by removing the clogged filter from the nozzle. To do this, use a special mechanical stripper.

The average cost of cleaning the injector

Cleaning the injector without removing the injectors on a running engine will cost the owner about 15-20 US dollars. The price of diagnostics and cleaning of one nozzle on the cavitation stand or in an ultrasonic bath costs about 4-6 у.о.. Replacement of a basket mesh microfilter and purchase of a repair kit, which includes rubber sealing rings, will additionally need from 5 to 10 у.о.. A set of work on flushing the injector and replacing individual elements is often accompanied by a warranty of up to 6 months or 10-15 thousand. Mileage.

Let's summarize

Quite obviously, that the injector is best diagnosed and flushed in advance, without waiting for noticeable changes in engine operation. This will ensure the absence of a number of undesirable consequences, which occur after prolonged use of the car with contaminated and / or faulty injectors.

Even regular refueling with the best fuel at elite gas stations does not rule out problems with the injector. Cleaning each individual nozzle on the stand ultimately provides the best effect. Each of the above methods of cleaning in practice is better than independent attempts to wash the injectors in the garage by soaking them in kerosene, diesel fuel, solvents, acetone or other liquids.

The undeniable advantage of the cavitation stand or ultrasonic bath is the ability not only to qualitatively remove dirt and return the nozzles to working order., but also to carry out the necessary diagnostics of injectors before the beginning of works on their clearing. In some cases, this allows you to timely detect faults in the nozzles and save money on flushing.

Finally, I would like to add, that the cost of cleaning the injector is quite affordable for the consumer, and a natural reduction in fuel consumption after such a procedure allows you to quickly recoup the amount spent. The owner can only enjoy the increased sensitivity of the power unit to depress the accelerator pedal and smooth operation of the engine in all modes!