Signs of malfunctioning injector nozzles

Most modern cars are equipped with injection engines; the days of carburetor engines are gone forever. Injection power plants are more economical, environmentally friendly and productive, but at the same time they have a more complex design and injection system, consisting of a pressure regulator, injectors equipped with an electromagnetic valve, a fuel line, a fuel rail, intake valves and a number of other parts.

During operation, various fine particles and heavy fractions (sulfur, olefin, benzene and a number of others) are deposited on the designated parts, which come along with the fuel and can accumulate in the form of varnish and resinous deposits. In turn, this leads to contamination of the injectors, a change in the direction and shape of the spray pattern, and in some cases a complete cessation of fuel supply, even when using fuel filters that are capable of filtering out particles larger than 10-20 microns.

As a result, the formation of the air-fuel mixture is significantly deteriorated, the tightness of the pressure regulator valve is also compromised, and engine performance is reduced.

The deposition of these substances can interfere with the normal functioning of the working elements inside the nozzle, namely, it can disrupt the tightness of the valve, which is opened by an electromagnet controlled by the BC. In this case, when closed, they will allow gasoline to pass through due to constant pressure in the fuel system.

Signs of injector contamination.

When the injectors of an injection engine of any vehicle become dirty, characteristic signs of malfunction arise, which necessitates the need to clean the engine injectors. Among these signs we note:

Difficulty starting the engine, especially as the outside temperature drops and the engine is cold;
Unstable engine operation at idle;
Perceptible dips when sharply or smoothly pressing the accelerator pedal;
Loss of acceleration dynamics and power by the motor;
Increased gasoline consumption;
Increased toxicity of CO-CH exhaust gases;
A several-fold increase in detonation when accelerating, which is a consequence of an increase in temperature directly in the combustion chamber and a depletion of the air-fuel mixture;
Misfires (ignition);
Periodic, characteristic popping sounds directly in the exhaust system;
Premature failure of sensors, including the catalytic converter, spark plugs and oxygen sensor (lambda probe).

It should be noted that even if all the problems listed above are present during the operation of your machine, this does not mean that the cause is clogged injectors. These problems can arise for a large number of reasons - from the failure of any sensor (air meter, throttle sensor, lambda probe, IAC) or a drop in pressure in the fuel system (RDT, fuel filter, fuel pump), to spark plugs.

Nozzle installation

Before dismantling the device, mark all parts with a marker to avoid confusion. Be especially careful about marking high-pressure hoses. The nozzle is screwed in by hand as far as you can. Further tightening is performed with a dynamometer wrench. The tightening values are indicated in the motor manual. When installing the injector, bleed the air from the fuel system. On modern cars, this is enough to turn the starter several times; or use a manual pump (if available).

The main causes of injector contamination.

The main, but far from the only reason for clogging of injection engine nozzles, is undoubtedly the quality of the fuel. In Western Europe, almost no one cleans injectors; manufacturers only recommend changing them after 120-150 thousand kilometers.

But the injectors of cars that are operated in the territory of the former USSR have to be cleaned every 15 - 30 thousand kilometers. There is only one reason for the poor quality of fuel - the desire to receive excess profits from the sale of fuel and lubricants. As a result:

Insufficient capacity for the production of A-92 and A-95 gasoline, but A-98 at domestic gas stations is in most cases a myth and a cunning marketing ploy - nothing more;
Violation of fuel storage conditions. Often, the same tanks are used to store gasoline A-76, A-80, A-92, A-95, A-98, in which various tar deposits accumulate over the years of operation, dissolved by fuel with a higher octane number. As a result, tar deposits are washed into the tanks of our cars, leading to failure of the fuel system;
The use of manganese-containing additives in the production of fuel, which increase anti-knock resistance. These are so-called anti-knock agents, which allow you to turn low-octane gasoline into high-octane gasoline with a slight movement of the hand. For example, an A-80 can “by magic” become an A-95, and there will be no detonation and its consequences as such. The additives, in turn, cause increased wear of the spark plugs and accelerated contamination of the fuel filter with fine brick-colored particles.

All these reasons lead to the need to replace spark plugs, clean the injector, and in some cases even overhaul the engine.

Basic diesel malfunctions.

Unfortunately, not everyone can afford to have a garage or a separate area for fuel storage. To clean the fuel, you can install a sediment filter or separator. This sump is capable of holding up to 150 g of water and dirt, thereby extending the life of your high pressure fuel pump and injectors. Method three Periodically perform diagnostics of fuel equipment. A malfunction noticed in a timely manner will allow for preventive repairs and prevent serious damage to the high pressure fuel pump and injectors of your diesel engine. Basic malfunctions of diesel injectors.

1. The injector nozzle is pouring (not spraying).

The injector nozzles have the fifth class of manufacturing accuracy. Such a precise detail completely eliminates the ingress of dirt and water. The sprayer is lubricated with diesel fuel. Damage to the working edge of the nozzle significantly impairs the quality of fuel atomization and distorts the direction of injection. Contrary to popular belief, injectors damaged by low-quality diesel fuel cannot be washed or cleaned. The malfunction can only be eliminated by replacing the nozzle. The main signs of a faulty injector are: a). Uneven engine operation - not all cylinders are working b). Blue smoke from the exhaust pipe and loss of power c). A strong knock similar to the knock of a connecting rod

2. Drop in injection operating pressure.

This occurs due to wear of the spacer shims or fatigue of the springs. This problem can be eliminated by adjusting the pressure on a specialized stand. A sign of this malfunction will be rough engine operation and the presence of black or bluish smoke.

3. Violation of the tightness of the nozzle body.

Body leakage occurs due to deformation of the edges of the adjacent surfaces of the injector body at the junction. This usually occurs due to repeated disassembly and reassembly of the injector. In this case, the housing must be replaced. On some Japanese vehicles that have a rigid return mount, it is possible to leak from under the washers. The reason may be damage to the seating plane of the return washers - in this case, the return washers are changed, the return frame and the nozzle body are straightened on a lathe.

Malfunctions of the Common Rail system injectors.

Unlike mechanical injectors, the malfunction of which has virtually no effect on starting a diesel engine, a malfunction of the Common Rail system injector is often the reason for the inability to start the engine. In addition to the above malfunctions, piezo injectors lose their hydraulic density, that is, the ability to maintain the required pressure in the system for a certain time. The nozzles of this system have a common pressure, and the loss of tightness of even one nozzle reduces the overall pressure in the system. On most cars with a Common Rail system, the minimum fuel pressure required to start the engine must be at least 130 Bar. If the pressure in the fuel rail is lower, the control unit will not give a signal to the injectors, and therefore the engine will not start.

TNDV – high pressure fuel pump. TNDV is a mandatory component and is present in any diesel engine. The main manufacturers of diesel fuel pumps are: Bosch, Denso, Zexel, Kiki, Lucas, Roto Diesel, Delphi. TNDV can be of a distribution type or with a common line (on more modern engines). Depending on the performance and technical parameters of fuel pumps, the technical and power indicators of diesel engines change. Despite the design features of different types of TNDV, they are all quite fragile and easily fail due to low-quality diesel fuel. A sediment filter, which you can install with us, will help prevent water and dirt from entering the pump. Attention! – TNDV is a high-tech unit and requires repair only at specialized service stations. Independent intervention in TNDV threatens costly repairs.

1. Common Rail injection pump

This is a fairly modern system with a common fuel line. Injection pumps for such a system are produced by Bosch and Delphi. Bosch fuel injection pump is a three-beam plunger pump, on many models with a switchable section. In our practice, the main malfunction of such a pump is low-quality fuel. Delphi fuel injection pump – rotary. The main malfunction of this injection pump is a violation of the cementation of the surface of the hydraulic head parts. This is also the reason why expensive injectors fail.

2. High pressure distribution pump.

Single-plunger injection pump with a high-precision kinematics system. Electronic control has been used on such pumps since 1992. The advantage of this type of injection pump is its unique maintainability. Almost all fuel injection pump parts are interchangeable and are almost always available in specialized stores. The injection pump is adjusted strictly on a specialized stand, taking into account the parameters prescribed by the manufacturer. There are many malfunctions in such fuel injection pumps and diagnostics can only be carried out at a specialized service station or at our technical center. Under no circumstances should you pour any additives into the tank that supposedly clean the fuel system. Such additives not only do not improve the performance of the fuel injection pump, but can also damage it.

How to check injectors without removing them from the engine

The injector is an electromechanical valve that acts as an electric magnet. When voltage is applied to the injector winding, an electromagnetic field arises that can retract the core and needle of the shut-off device, while allowing a flow of fuel to the engine combustion chamber. An additional fuel filter is mounted on the input channel of the devices.

The injector is the final element of the fuel system, into which fuel enters under high pressure. The entire operation of an internal combustion engine directly depends on the performance of this component. When the pressure level drops when opening the injector, it opens earlier, which causes black smoke to form. If the pressure at the moment of opening increases, then it opens later and white smoke appears.

What functions does an injector perform in a car?

Absolutely all modern internal combustion engines, both diesel and gasoline, have a fuel injection mechanism. The nozzle in this system plays the role of a pump, supplying a very thin stream of fuel under high pressure and being one of the main elements of the injection system.

An engine injector is an electromagnetic valve that operates in accordance with a special program embedded in the engine control unit. This valve ensures a dosed supply of fuel to the cylinders. And today an injector means precisely an organized system of nozzles.

By purpose, these elements can be:

for distributed injection;
for central injection;
for direct injection.

Fuel is supplied to each injector under a certain pressure due to the supply of electrical impulses from the control unit to the electromagnet. These pulses respectively open and close the needle valve at the right moments and thus regulate the flow of fuel through the nozzle channel into the cylinder. The longer the pulse lasts, the longer the valve will be open and the more fuel will flow into the injection element. The duration is regulated by the engine control unit. In addition to the duration of fuel supply, the nozzle mechanism allows you to create different shapes of the fuel torch and produce a jet at different angles. These variable parameters have a significant impact on the creation of the fuel mixture in the engine.

Not all car owners can immediately find an injection system in the engine. The location of the injectors depends on the type of injection used in a particular case:

With a central injection scheme, 1-2 nozzles are located in the intake manifold near the throttle, completely replacing the carburetor.
In a distributed scheme, each cylinder is equipped with a separate injector. In this case, the injector is located near the base of the intake manifold, where fuel is injected.
In the direct scheme, the injector is placed on the cylinder walls in the upper part. Injection is carried out directly into the combustion chamber.

Thus, injection elements are an important component of a modern engine, the uninterrupted operation of which completely depends on these elements. Therefore, the injector needs periodic inspection and flushing.

Signs of injector failure

1. The operation of the engine starting elements slows down, which is especially pronounced in cold weather.

2. The occurrence of dips and some twitching of the car at the time of acceleration or change of transient modes.

3. Poor dynamics and reduction in engine power.

4. The amount of fuel consumed increases.

5. When idling, the car engine may run unevenly.

To avoid untimely car repairs, you should promptly check the performance of the injectors.

Why an engine injector leaks: causes and repairs

Issues discussed in the material:

What is the purpose of a fuel injector?
Why might an injector leak on a gasoline or diesel engine?
How to determine if an engine injector is faulty
Is it possible to repair an injector if it is leaking?

The fuel injector is the main component of the power supply system of a gasoline or diesel engine. Its main task is to provide direct fuel supply to the intake air tract chamber or directly to the engine cylinders by spraying. The fuel injector can become a source of problems if it leaks fuel. We will tell you why the injector is leaking and how to fix this problem in our article.

How to check injectors without removing them from the engine?

Checking the winding resistance level on the injectors

1. You can carry out an inspection by turning off the ignition and removing the negative terminal from the battery.

2. Using a thin screwdriver or an awl, you need to unclip the spring clip on the block.

3. Disconnect the connector from the injector.

4. Attach an ohmmeter to the injector terminals and measure the winding resistance.

5. If the resistance between the side and central pins of the connector is within 11–15 Ohms, then the injector is working properly. If the device shows more or less than required, it should be changed.

Checking the functionality of all injectors

1. Initially, you need to remove the fuel rail on which the injectors are installed.

2. Then you should connect the wire block to the ramp harness. If the “-” terminal was removed from the battery, then put it back on.

Checking diesel injectors for overflow (drain to return)

Checking the volume of return flow

As diesel injectors wear out over time, a problem arises due to the fact that the fuel from them gets back into the system, due to which the pump cannot generate the required operating pressure. The consequence of this may be problems with starting and operating the diesel engine.

Before the test, you will need to buy a 20 ml medical syringe and an IV system (to connect the syringe you will need a 45 cm long tube). To find an injector that throws more fuel into the return line than it should, you need to use the following algorithm:

remove the plunger from the syringe;
with the engine running, use the system to connect the syringe to the “return” of the injector (insert the tube into the neck of the syringe);
hold the syringe for two minutes so that fuel is drawn into it (provided that it will be filled);
repeat the procedure one by one for all nozzles or build a system for all of them at once.

Based on information about the amount of fuel in the syringe, the following conclusions can be drawn:

Checking the return flow

if the syringe is empty, it means the nozzle is fully operational;
the amount of fuel in a syringe with a volume of 2 to 4 ml is also within normal limits;
if the volume of fuel in the syringe exceeds 10.15 ml, this means that the injector is partially or completely out of order and needs to be replaced/repaired (if it pours 20 ml, then it is useless to repair, since this indicates wear of the injector valve seat ), since it does not maintain fuel pressure.

However, such a simple check without a hydraulic stand and plan test does not give a complete picture. Indeed, in fact, when the engine is running, the amount of fuel discharged depends on many factors; it can be clogged and needs to be cleaned, or it freezes and needs to be repaired or replaced. Therefore, this method of checking diesel injectors at home allows you to only judge their throughput capabilities. Ideally, the amount of fuel volume they pass through should be the same and range up to 4 ml in 2 minutes.

To ensure that the injectors last as long as possible, refuel with high-quality diesel fuel. After all, it directly depends on the operation of the entire system. In addition, install original fuel filters and do not forget to change them on time.

Checking the power supply to the injectors

Such a check must be carried out only when at least one of the injectors refuses to work when the ignition is turned on.

1. Disconnect the block with wires from the non-working part.

2. Then connect the two ends of the wires to the battery, and attach the other side to the contacts on the injector.

3. Turn on the car's ignition and check to see if fuel is leaking from the injector. If yes, then there is some kind of defect or malfunction in the electrical circuit.

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Checking the injector balance

To balance the fuel pump, you must first turn off the fuel pump and start the car. After a few seconds of operation, the engine should stall - this is necessary to eliminate excess pressure of the mixture. Then the pressure gauge is connected, and only after that the fuel pump returns to its place. Next, a computer with the necessary software is connected and diagnostics are carried out.

Subsequent actions are performed exclusively using specialized programs. You may notice that the fuel pump will gradually turn on and off, as will the injectors. In general, the following algorithm can be distinguished:

Turning on the ignition;
Pressure gauge readings are in the range of 2.8–3 atm;
The fuel pump turns off;
Pressure drop to 2.5–2.8 atm;
Checking one TF;
Analysis of pressure gauge data – significant dynamics should not be observed;
The pressure is restored to its original value by turning on the fuel pump;
The procedure is repeated one by one with all nozzles.

When working correctly, each element will give approximately the same performance. If the reset is different in a certain place, then we can talk about a malfunction of the injector or its further diagnostics. After completing the manipulations, the pressure gauge must be turned off only after first releasing the pressure in the system.

How to understand what is wrong with the VAZ-2114 engine

The concept of “engine tripling” was invented by motorists themselves. It is associated with the design and operation of four-cylinder internal combustion engines. If one of the four cylinders failed, the internal combustion engine still continued to operate on the three remaining cylinders. But such a failure was distinguished by a characteristic sound, which was called “engine tripping” - functioning on only three cylinders. In this case, the fuel mixture in the idle cylinder will not burn as expected, but will accumulate.

If you do not respond to such a failure in the system in time, the fuel mixture will be diluted with oil, enter the crankcase with oil and dilute it thinner and thinner. In this case, the oil will lose its lubricating functions, which will lead to rapid wear of the rings, cylinder-piston group and other important parts of the car. A little later, the engine will have to be repaired not partially, but completely.

Similar failures occur in the VAZ-2114. They can be recognized by their characteristic features:

The engine in idle mode manifests itself with periodic twitching, unevenly.
When driving, the VAZ-2114 does not gain the required power.
The car moves jerkily.
If you press the gas pedal, failures in engine operation will be detected.
An uneven exhaust comes out of the muffler, which is interrupted and accompanied by popping noises.

Against the background of these signs that the VAZ-2114 engine is failing, the driver may notice an increase in fuel consumption.

Nozzle repair

The injector can be repaired by yourself. The easiest way is with mechanical injectors. In this case, you can decide to repair it yourself, having a standard set of tools.

The repair process for injectors from different manufacturers differs markedly.

Bosch Common Rail injectors are easy to repair. The most common malfunctions of such injectors are damage to the atomizer and multiplier (valve). The multiplier fails more often, the atomizer - less often. The manufacturer provides a guarantee for the sprayer, obliging to replace it if it fails before after 100 thousand kilometers. In Russia and the countries of the former CIS, due to low quality fuel, nozzles become faulty after 20 thousand kilometers.
Bosh injector is easy to repair
Delphi injectors also have two “weak” points - the valve mechanism and the atomizer. The latter is cleaned with ultrasound or replaced with a new one.
The Japanese company gives a 150 thousand km warranty on its injectors. In addition, they are cheaper than their European counterparts. However, components for Denso injectors are not commercially available. Therefore, the only solution is to replace the faulty injector.

Article on the topic: Vandal-proof instructions: how to protect your car from draining gasoline?

Required Tools

To repair injectors you will need:

clean, lint-free cloth;
flat blade screwdriver;
spanners;
tweezers for removing petals;
side cutter or pliers for removing the mesh;
hex key.

Disassembling the nozzle

The nozzle is disassembled as follows.

The nozzle is clamped in a vice.
Using a wrench, you turn out the valve, under which there is an adjusting washer, a spring and a rubber ring. It is recommended to handle the ring carefully as it is not available for sale.
The nozzle is clamped in a vice and the valve is turned out with a wrench
Use tweezers to remove the nozzle petals.
Using tweezers or a thin screwdriver, remove the nozzle blades
The spring is removed.
The large ring is removed.
Use a hex wrench to unscrew the nut with an M17 external thread.
The nozzle is pulled out. The animator is knocked out of it by tapping.
The sprayer (on the left) is not removable, the multiplier (on the right) is removable
Using a screwdriver, remove the nylon washer and copper ring from the nozzle cavity.

Video: disassembling the Delavan injector

Replacing O-rings

O-rings are sold as a repair kit. They are installed in the injector multiplier and prevent air from entering from outside. As they wear out, the seals lose their elasticity and begin to leak air. The injector begins to inject fuel poorly, which, in turn, leads to unstable engine operation.

The injector O-rings are lubricated with oil before installation.

The algorithm for replacing seals looks like this.

The rings are removed from the nozzle. If the rubber has hardened, they are cut off with a sharp knife.
New rings are coated with engine oil and installed in place of the old ones.

Possible reasons

It turns out that there are quite a lot of reasons for such a malfunction in the VAZ-2114 engine. They directly depend on the nature of the vehicle malfunction. So, most often the VAZ-2114 engine will triple due to:

non-working candle;
broken high-voltage wire;
ignition coil failure;
faulty control unit;
presence of air leaks in the intake manifold;
exhaust valve burnout;
broken cylinder head gasket;
broken compression rings on the piston;
burning out of the piston itself;
a broken piston bridge between the compression rings.

But since we are considering a VAZ-2114, the engine can also be damaged by faults in the injector - a fuel system with distributed injection.

Why is the injector leaking?

Why does the nozzle on an injection machine leak? Because the o-rings have deteriorated. Let's talk about this in more detail.

Rubber O-rings are used to eliminate air leaks and fuel leakage at the point where the injector is connected to the fuel line, in other words, for sealing. They can have an x-shaped, round or rectangular cross-section. They can be elastic, rigid, resistant to temperature changes, the negative effects of aggressive environments and various chemicals.

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1. Seals on different types of injectors.

Self-ignition of the working mixture occurs due to the high degree of compression; the load on the cylinder-piston group is high. A common mechanical pump injector is screwed into the cylinder head; to ensure a tight seal, a soft metal washer is used, installed on the bottom of the landing well. Copper is most often used, less often aluminum alloys. The metal must be soft and deform when tightened to ensure a tight seal.

Injection is carried out through a mechanical drive from the camshaft through pushers with rocker arms. Fuel is supplied through a metal pipeline; the return drain line is sealed with copper washers on the fittings.

Modern interpretations of this part are controlled electronically, which makes it necessary to significantly increase the fuel inlet pressure. This led to the need to use additional seals.

Inlet or upper o-rings are found on both gasoline and diesel injectors. They serve to eliminate air leaks and fuel leakage at the point where the injector is connected to the fuel line. They are most often made of rubber, since there are no large mechanical and temperature effects. However, the requirements for the material of the rings are high in terms of elasticity and its preservation under the influence of aggressive environmental factors.

The lower seal operates under more severe conditions, so the following options are possible:

one metal ring;
one rubber, made of a special composition, capable of withstanding temperature and mechanical stress;
metallic and elastic at the same time;
no one.

2. Symptoms of faulty o-rings.

It is often quite difficult to determine what caused the damage and failure of the o-ring - errors in design, improper installation or non-compliance with operating conditions. Sometimes a malfunction can be caused by several factors acting simultaneously. As a rule, damage to the upper seal is detected by fuel leaks. It could just be a wet spot, drops or even a trickle. Leakage of fuel here is very dangerous due to the possibility of it flowing down onto the hot output manifold, which definitely leads to a fire; urgent replacement is required.

If the lower seal is faulty, air leaks in and the mixture becomes lean. The engine starts only when the gas pedal is partially pressed, idles unstably, and power decreases, especially at low speeds.

With high mileage, the rings, especially the lower ones, due to high temperatures, can simply become stiff and lose elasticity. Then the smell of gasoline appears in the cabin at low temperatures when starting. The replacement may wait a little, but you shouldn’t delay it for too long.

On some diesel engines, leaks in the lower o-rings lead to gases breaking through and entering the oil. Coke is formed, which is washed into the oil pan and clogs the oil receiver. The main symptom in this case is white acrid smoke within a few seconds after starting, and when the malfunction occurs, the oil pressure lamp blinks. This car cannot be used; faulty parts need to be replaced.

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3. When to change the seals on the injectors.

What to do if the engine on a VAZ-2114 is malfunctioning

To understand the causes of malfunctions in the VAZ-2114 engine, you need to know its configuration. He has:

there are eight valves in the cylinder head;
1.6 liter internal combustion engine with 16 valves.

Experts advise that at the first signs of tripping, immediately check the functioning of the spark plugs. To do this, carry out the following steps:

One by one, pull off the high-voltage wires from the cylinders.
Pay attention to changes in engine operation:
if there are no changes, the cylinder does not work.

The next step is to check the spark in the ignition system. This procedure is also simple:

The first step is to remove the tip from the high-voltage wire.
While the car engine is running, bring the wire from the cylinder head (ground) to the “break” position.
Check for a spark between ground and wire:
If there is no spark or the spark is too weak, then the ignition system is faulty.

But the following situation also happens: the spark is powerful, but malfunctions are still heard in the engine. This means that the time has come for the next step of testing - to measure compression in the cylinders, preferably in all of them at once. If the cylinder is operating correctly, there should be no difference in the pressure gauge readings (minor deviations are allowed). If the cylinder is faulty, there will be no or very weak compression.

A malfunction in the cylinder may be due to one of the following reasons:

cylinder head gasket is broken;
exhaust valve burnt out;
piston rings burst;
The piston itself burned out.

If you are unable to independently identify the reason that the VAZ-2114 engine is malfunctioning, you definitely need to do computer diagnostics. This can be done in two ways:

On a special computer stand.
Using a portable scanner (for example, ASKAN).

An experienced motorist himself will be able to figure out the malfunctions of the VAZ-2114 engine, but if he does not have sufficient experience, then it is best to contact qualified specialists at a service center for servicing cars of this model.

Washing without dismantling

There are different ways to clean an injector. At a car service center, I can offer you both flushing at a stand and a cheaper method, flushing using a special device that simulates the action of a gas pump. It connects to the car’s fuel rail and delivers cleaning fluid under pressure to the injectors; the engine runs only while flushing, after which the injectors can be considered clean. This method has several disadvantages; it is impossible to evaluate the quality of the spray and the degree of contamination of each nozzle. The method is budget-friendly and quite easy to implement with your own hands, instructions below.

I would also like to note the addition of cleaning additives to the fuel. Many manufacturers such as “Suprotek”, “Lavr”, “Wins” produce these washes and you can even buy them in supermarkets. I wouldn't call this method effective. The additive cleans deposits from the entire fuel line and after its use it is recommended to replace the fuel filter, since it will absorb all the dirt, but this liquid cannot dissolve tarry deposits in the injectors. If you haven’t cleaned the injectors for a long time, then this method will not help you. This is just prevention.

Checking the engine at idle

If you notice that the VAZ-2114 engine starts to stall at idle, then you need to check the following systems:

Fuel supply system.
Ignition system.
Valve system.

In the first case, if the faults are in the fuel supply system, then the first step is to flush the fuel system, and then clean the injectors using ultrasound.

The second case involves problems with the ignition system. Therefore, perform the following actions:

change spark plugs;
check the functionality of the ignition coil;
update the set of high-voltage wires.

In the third case, the valves are closely dealt with, that is, they should be adjusted so that they perform their functions properly. If this cannot be done, the old valves are simply replaced with new ones.

How to wash injector nozzles with your own hands

-channel “Mikhail Nesterov”

There is a solenoid needle valve located inside the fuel injector body. It is held closed by a return spring. When pulses are supplied from the electronic control unit (ECU) to the excitation winding, the valve opens. At this moment, the fuel is atomized and mixed with air, burned in the combustion chamber.

The correct proportions of the air-fuel mixture and its ignition depend on the quality of gasoline atomization. During normal operation of the injectors, the fuel is crushed into small particles, easily mixed with air and burned.

Why do injectors clog?

Impurities in the fuel, short trips and difficult operating conditions lead to carbon deposits forming on the needle and internal surfaces of the injector. This plaque clogs the channels. The solenoid valve opens for a long time and more gasoline enters the combustion chamber than necessary.

-channel "Auto-topic"

All this leads to an over-enrichment of the fuel mixture, poor ignition and misfires. Unburnt gasoline enters the exhaust system and burns out inside the catalyst, which becomes clogged and melts at high temperatures. At the same time, engine power decreases, detonation appears, and fuel consumption and exhaust toxicity increase.

How to understand that you need to flush the injectors

Car manufacturers recommend cleaning every 30 thousand kilometers. Problems with the injectors will be indicated by corresponding errors on the on-board computer. The same thing will be shown by diagnostics of fuel equipment in a car service center.

But with a high probability, flushing is needed regardless of mileage, if at least three symptoms from the list appear in your car:

poor starting (especially in winter);
unstable operation at idle speed;
reduction in engine power;
slow acceleration;
dips when pressing the gas pedal;
increased fuel consumption.

Method 1: fuel additive

Typical bottle of fuel additive for flushing / drive2.ru

The simplest and relatively gentle cleaning method is using special additives. More suitable for preventing the formation of deposits inside all elements of the fuel system - from the gas tank to the injectors.

The disadvantage of such additives is that on cars with high mileage they lift all the dirt from the gas tank and pipelines. As a result, the filters and the injectors themselves become clogged, which leads to even more disastrous consequences.

You will need

Fuel additive-injector cleaner.

How to do

Pour the product into the tank immediately before refueling according to the proportions in the attached instructions.
Operate the vehicle as normal.
For the best cleaning effect, it is advisable not to stand in city traffic jams, but to drive along the highway.

Method 2: flushing the injectors on the engine

This cleaning method is more difficult, but also more effective. It not only cleans the injectors, but also additionally decarbonizes the piston rings and also increases compression. Flushing is carried out with the engine running, which runs on detergent instead of gasoline.

The main disadvantage is that the quality of washing cannot be controlled. Other disadvantages include the entry of aggressive substances into the exhaust tract and potential damage to the catalyst. After using some products, spark plugs may need to be replaced.

How to restore the performance of a VAZ-2114 engine: expert advice

Automotive repair experts recommend that motorists use several tips to restore the functioning of a VAZ-2114 engine that is tripping.

First tip: check and replace the electronic control unit.

Second tip: check and replace the oxygen sensor.

Third tip: check the functionality of the crankshaft position sensor. This can be done using the electronic control unit. This device will generate an error if the crankshaft position sensor is faulty. This means you will have to replace it with a new one.

Fourth tip: check and replace the ignition coil.

Cleaning and flushing diesel injectors - the main differences

Cleaning diesel injectors is not a difficult task; the process repeats the cleaning of gasoline injectors; there are not many main differences, but they still exist and are quite significant.

The design of a diesel injector and the principle of its operation.

Firstly, signs of contamination of diesel injectors include loud engine operation; the same cannot be said about gasoline engines.

Additives and various cleaners for diesel injectors are sold in the same quantities as for gasoline engines.

You can also clean the injectors with ultrasound or using a special stand; you can make an improvised tank and connect it to the injection pump instead of the main fuel line.

VAZ 2114 car injector system

The VAZ 2114 is equipped with an engine with a distributed fuel injection system (injector), and the stable operation of the engine of this car depends on the quality of gasoline. A low octane number of fuel leads to a drop in power and unstable operation of the power unit. As a result, any parts of the internal combustion engine (ICE) may fail. Mechanical impurities in fuel lead to clogging of fuel filters. the fuel pump is damaged. the injectors are clogged. You have to disassemble the fuel system (TS) and clean the injector. How the VAZ 2114 injector works, how to clean it and in what cases, how to remove and install the fuel rail, we will look at in this short article.

The VAZ 2115 injector is no different from the VAZ 2114, so when considering the device of the “fourteenth” model, we will also keep in mind the “15th”. The mechanical part of the injector includes:

Intake manifold;
Fuel rail (or rail, which is the same thing);
Throttle assembly;
Air filter with housing;
Air pipe (injector corrugation);
Injectors.

Gasoline injector device

Car enthusiasts who replace the carburetor with a distributed injection system in their “eights” and “nines” are puzzled by purchasing exactly these listed parts, not counting the electrical components.

The injectors on the VAZ 2114 are an electromagnetic device in which, when there is a pulse in the electrical component, a valve opens. and atomized fuel is injected under pressure into the internal combustion engine cylinder. Depending on the magnitude of the pulse, the valve opens to a greater or lesser extent, thereby dosing the flow.

Model 2114 can be equipped with fuel injectors from different manufacturers, and accordingly, the cost of the injectors may also differ. Manufacturers and cost (price range in the Russian Federation):

GM (1300 - 1400 rub.),
BOSCH (1000 - 1200 rub.),
SIEMENS (800 - 1400 rubles).

The VAZ 2114 (2115) is equipped with engines of 1.5 and 1.6 liters (8 and 16 valves), therefore the performance of the injectors must be selected depending on the type of engine. If you make the wrong choice, fuel consumption may increase or the internal combustion engine may lose power. Which injectors are better to install on a VAZ 2114? Here you should focus on the part markings. For example, BOSCH 0 280 158 502 is only suitable for a 1.5 l 8-valve engine. It’s hard to say anything about the manufacturer; the quality of all products is approximately the same.

Symptoms of a problem

There are certain signs of clogged injector nozzles:

Difficulties in engine operation, jerking;
High gas consumption;
Unstable engine operation at idle speed.

And, if the injectors are leaking, the internal combustion engine may not start at all. To improve engine operation, you should clean the injectors on the VAZ 2114.

Let's look at how to remove injectors on a VAZ 2114 (of course, everything is done with the engine not running, and it won’t hurt to disconnect the battery terminals). To do this we need a set of combination wrenches, a hexagon, screwdrivers and pliers:

Relieve the pressure in the system. On the rear of the ramp there is a valve under the cap. We unscrew the cap and press the valve with a thin screwdriver or rod.
Remove the air filter pipe;
Disconnect the fuel lines (supply and return);
Disconnect the electrical connectors from the injectors. The connectors are snap-on and easy to remove;
We unscrew the two ramp mounting bolts (or a 10mm wrench or a hexagon):
We dismantle the fuel rail.

Move the latch and take out the nozzle

The injector is removed from the ramp very simply - you need to move the locking washer to the side and pull out the injector using a little force.

Replacing injectors with the fuel rail removed is done simply - remove the old part, install the new one and secure it with a springy split washer. Then we install the fuel rail in place. Changing the nozzle is very simple.

Before cleaning, it won’t hurt to check the injectors on the VAZ 2114; it’s a good idea to first make sure they are not working. The check is carried out on a removed fuel rail; there is a special stand for this; many modern car repair shops are equipped with such stands.

You can check each individually removed injector by applying power to it and connecting a fuel tank to the inlet. When voltage is applied, the valve should operate and gasoline should spray out of the nozzle. But the test here is conditional; performance is almost impossible to determine.

Even more dubious is the idea with measuring cups, which is often described on resources on the Internet. Let's say all glasses are filled with the same amount of gasoline. How then did you determine the performance when simply cranking with the starter? After all, the engine operates at different speeds, and a faulty injector usually overflows gasoline depending on the voltage supplied to it. What if the electrical part is faulty?

Cleaning VAZ 2114 injectors is carried out mainly by removing parts, but you can try flushing the system with special fuel. The fuel supply hose is disconnected and a container with solvent is connected to the injector (a plastic “one and a half” can be used), pressure is created by an external electric pump. Remove the power connector from the “original” fuel pump. It is better if the injector cleaning (flushing) is carried out in a car service - doing such work with your own hands is quite troublesome, and it does not justify the money spent on it.

You can clean the injectors on a VAZ 2115 with your own hands with the fuel rail removed. A container with a special liquid for flushing carburetors is fitted to the fuel inlet of the injector, and power is supplied to the electrical connectors. When power is applied, the valve in the nozzle will work and it will spray this liquid. Do-it-yourself cleaning of VAZ 2114 injectors is also done.

The idea of cleaning injectors with your own hands is not always justified on VAZ models.

Expensive foreign cars make sense - the parts on them are expensive. And at VAZ, the cost of flushing and lost time will be more expensive than buying new spare parts. In addition, the results of cleaning are not guaranteed to be positive.

Malfunctions of the injector (nozzles) occur on both diesel and gasoline engines. In the design of the power supply system of an injection engine, the nozzle is an element that is responsible for injecting a sprayed portion of fuel into the combustion chamber under a certain pressure.

Precise dosing, tightness and timely operation of the injection nozzle ensure stable and proper operation of the engine in all operating modes. If the injector “flows” (passes excess fuel at a time when its supply is not required), the efficiency of fuel atomization decreases (the shape of the torch is disrupted) and other injector malfunctions occur, then the engine begins to smoke gray or black smoke, loses power, consumes a lot of fuel and etc.

Why, if the injector is pouring into the cylinder of a diesel engine, it is better to contact a service station

The modern injection element in a diesel engine is a very precise mechanism capable of operating at elevated temperatures with fuel of the appropriate quality. And one of the problems that diesel owners face is that the injectors begin to leak into the cylinders. When contacting a car service center with this problem, people often cannot clearly justify their confidence that it is the injector that is faulty. After all, without special equipment, it is almost impossible to determine that the injector is pouring into the cylinder. And external symptoms of injector malfunctions are often indistinguishable from signs of problems in the fuel system of a diesel engine.

Most modern diesel cars are equipped with Common Rail fuel systems from Bosch, Delphi or Denso. The components of these systems are highly sensitive to the quality of the diesel fuel used. Even a small proportion of mechanical impurities causes the injector to pour into the cylinder. Signs of a diesel engine malfunction (namely the injection system) will coincide with those described earlier. The source of problems is jammed or failed parts, as well as an increase in the diameter of the injector nozzle. At the same time, the engine suddenly begins to “trouble”, and black smoke pours out of the exhaust pipe. If the injector is pouring heavily into the cylinder and does not atomize fuel, this can lead to a more serious problem - melting of the pistons.

As already mentioned, when the injector pours into the cylinder, the pressure in the system drops below the minimum allowable. The solution to the problem depends on two points. In the first case, the injector pours in the opposite direction, in the second case it pours into the cylinder. Correctly identifying the true cause of a diesel fuel system malfunction can only be done through diagnostics at a special stand. Based on the identified problem, the issue of repairing the nozzle or replacing it completely will be decided.

It is not recommended to fix the problem with a diesel injector pouring into the cylinder yourself. The fact is that during the repair process the nozzle is completely disassembled and during reassembly it is necessary to strictly observe the regulated dimensions and tightening torques. Deviation of at least one parameter can lead to imbalance in the operation of the injector, as a result of which the pistons can burn out. If the injector flows “into the return” and not into the cylinder, it is tested on a bench. The tests consist of determining the amount of fuel poured in the opposite direction over a certain time interval for each injection element. The obtained data is checked against the manufacturer’s passport values.

Which indicates possible problems with the injector

Let us immediately note that there can be many reasons for unstable engine operation, ranging from a clogged fuel filter, a broken fuel pump, a failed spark plug or a faulty coil, to loss of compression, problems with the timing belt, etc. Along with this, one of the main signs of injector malfunction is difficulty starting the engine, especially when cold, as well as gasoline or diesel consumption (depending on the engine type), which increases noticeably. It is also necessary to note the unstable operation of the internal combustion engine in idle mode, similar to the so-called “triple” of the engine.

When driving, it is possible that one or several symptoms may occur quite frequently:

presence of jerks, very slow reactions when pressing the gas pedal;
obvious failures and loss of dynamics when trying to accelerate sharply;
the car may jerk while driving, when releasing the gas, and also after changing the load mode on the engine;

It must be added that such a malfunction must be corrected immediately, since problems with the injector negatively affect not only the service life of the engine and transmission, but also overall traffic safety. In a vehicle with faulty injectors, the driver may experience serious difficulties when overtaking, on steep hills, etc.

Increased fuel consumption

If the injector springs are damaged, fuel will flow into the cylinders even when it is not needed, and will also flow in greater quantities than necessary. This will undoubtedly have a serious impact on the fuel consumption and smoke emissions of a diesel vehicle.

Pay attention to the signs described. By paying attention to the things described above in advance and visiting Diesel Service in a timely manner, you will save a large amount of your time and money.

Read in this article

Self-check of injectors

Let's start with the fact that automobile injectors are divided into several types, of which two types have found widespread use at different times: mechanical injectors and electromagnetic (electromechanical) injectors.

Electromagnetic injectors are based on a special valve that opens and closes the injector to supply fuel under the influence of a control pulse from the engine ECU. Mechanical injectors open as a result of increased fuel pressure in the injector. Let us add that modern cars often have electromagnetic devices installed.

To check the injectors with your own hands without removing them from the car, you can use several methods. The simplest and most affordable way to quickly check injection nozzles without removing them from the car is to analyze the noise emitted by the engine during operation.

Why don't the injectors work?

Nowadays, injectors are made to a tolerance of 1 micron, which allows them to carry out about a billion cycles. The main reason why their performance is impaired is contamination during operation , despite the fact that the path to any mechanical particles is blocked by filters that filter out particles larger than 10-20 microns. The place where the filters are installed is the fuel line and the injector itself. The main cause of contamination is the inevitable presence of heavy particles in the fuel. The largest accumulation of dirt occurs after the engine is turned off. At this moment, due to the fact that the nozzle is heated by the engine, the temperature of its body increases, while there is no cooling effect of the fuel. Light particles of fuel located in the nozzle evaporate, while heavy ones settle like varnish deposits, reducing the cross-section in the calibrated channel. For example, deposits 5 microns thick can reduce the capacity of a given channel by about 25%. Contamination of the holes in the injectors prevents the formation of the fuel mixture, the shut-off valve of the pressure regulator loses its tightness, and the high-pressure fuel pump in diesel engines reduces its performance.

How to check the power supply to the injectors

This check is carried out if the injectors themselves are working, but any of the injectors do not work when the ignition is turned on.

for diagnostics, the connector is disconnected from the injector, after which two wires need to be connected to the battery;
the other ends of the wires are attached to the injector contacts;
then you need to turn on the ignition and record the presence or absence of fuel leakage;
if fuel flows, then this sign indicates problems in the electrical circuit;

Another diagnostic technique is to check the injector using a multimeter. This method allows you to measure the resistance on the injectors without removing them from the engine.

Before starting work, you need to find out what impedance (resistance) the injectors installed on a particular vehicle have. The fact is that there are injection nozzles with both high and low resistance.
The next step is to turn off the ignition and also reset the negative terminal from the battery.
Next you will need to disconnect the electrical connector on the injector. To do this, you need to use a screwdriver with a thin tip, with which you need to unclip a special clip located on the block.
After disconnecting the connector, switch the multimeter to the desired operating mode for measuring resistance (ohmmeter), connect the contacts of the multimeter to the corresponding contacts of the injector to measure impedance.
The resistance between the outer and central contacts of a high-impedance injector should be between 11-12 and 15-17 ohms. If the car uses low resistance injectors, then the indicator should be from 2 to 5 Ohms.

If obvious deviations from acceptable standards are noticed, then the injector must be removed from the engine for detailed diagnostics. It is also possible to replace the injector with a known good one, after which the engine performance is assessed.

How to determine if an injector is not working on a running engine

Let's say you found a sign of a faulty injector and now want to know how to check your engine injectors? I would like to immediately note that the injectors themselves come in several types (mechanical and electromagnetic) and their design has significant differences, which means their testing methods should also differ. You can check injectors using several methods: checking injectors without removing them from the engine, checking removed injectors, checking injectors at home, checking gasoline or diesel injectors, etc. We will analyze the most popular methods.

To find out how to check the functionality of the injector nozzles, it is not necessary to remove them. This method is one of the simplest checks and involves a sound test (or analysis of the noise emitted by the motor during operation). As a rule, clogged or damaged injectors produce a muffled high-frequency noise (the sound usually comes from the cylinder block).

Checking the power supply to the injectors

Checking the power supply to the injectors is carried out if the injectors themselves are working when any of the injectors break down. To check it is necessary to carry out the following procedure:

disconnect the pads;
connect 2 wires to the battery, the end of which is fixed to the injectors;
turn on the engine.

After turning on the engine, you need to pay attention to the possible leakage of the fuel mixture - this may occur due to faults in the electrical circuit.

Checking the resistance on the winding with a multimeter (tester)

Checking the resistance on the winding with a multimeter (tester) also allows you to check the engine injectors without removing them. To do this, you need to make sure the resistance level of your injectors. Next we perform the following steps:

with the engine off, disconnect the negative terminal from the battery;
then disconnect the electrical connector on the injector itself (located on the block, in the form of a clamp);
We set the value of our injectors on a multimeter and connect its contacts directly to the injector itself.

Normally, at high impedance the value should be 11-17 Ohms, at low impedance 2-5 Ohms. If the values do not match, the injector must be replaced.

Analysis of the operation of injectors on the ramp

This method already involves dismantling the fuel rail. The injectors, of course, are removed along with the ramp. Then reconnect all electrical contacts to the ramp (after all, they are thrown off during dismantling). The negative terminal of the battery, which was removed earlier, also returns to its place.

Further:

the ramp is placed in the engine compartment so that it is possible to place a container with a printed scale under the injectors;
the fuel supply hoses are connected to the ramp (be sure to securely fix them at the ends);
the engine is started by the starter (it is advisable to work together with an assistant);
while the assistant rotates the starter, you need to test the operating efficiency of all injectors (gasoline must be supplied equally to all injectors);
at the last stage of the procedure, the ignition is turned off, the level of gasoline in the containers is checked (obviously, the level should be the same).

Anyone can check the injector nozzle with their own hands. It is not necessary to go straight to a car service center if you encounter another problem. An experienced motorist should be able to do some repairs himself.

Video: how to check the common rail injector without removing it from the engine

If such symptoms occur, you need to check the injectors, as one of the most likely causes of their occurrence. This can be done using different methods; for example, many specialists remove these components and check them. But there are techniques that allow you to determine whether the injector is working without removing it. You can do this yourself, and to perform diagnostics you will only need one device, and you will not need to disassemble anything.

Comprehensive diagnostics of the operation of injectors on the ramp

For such a check, the fuel rail will need to be removed from the engine along with the injectors attached to it. After this, you need to connect all electrical contacts to the ramp and injectors if they were disconnected before removal. It is also necessary to return the negative terminal of the battery to its place.

The ramp must be placed in the engine compartment so that a measuring container with a scale can be placed under each of the injectors.
It is necessary to connect the fuel supply pipes to the ramp and additionally check the reliability of their fastening.
The next step is to turn on the ignition, after which you need to crank the engine a little with the starter. This operation is best performed with an assistant.
While an assistant rotates the engine, check the efficiency of all injectors. The fuel supply must be the same on all injectors.
The final step will be to turn off the ignition and check the fuel level in the containers. The specified level must be equal in each container.

In addition to self-checking, you can use the injector diagnostic service at a car service center. This operation is performed on a special testing stand. Testing an injector on a bench allows you to accurately determine not only the efficiency of fuel supply, but also the shape of the torch during fuel spraying.

Why do injectors on a diesel engine fail?

The injectors on a diesel engine come out faster than on a gasoline engine. This is due to the fact that these motors have different operating principles. But in both cases, the culprit is low-quality fuel or untimely replacement of the fuel filter. If you service the car on time, the injectors should work for at least 150,000 km without replacement or repair. If you also use high-quality fuel, then the factory injectors should last 200-300 thousand km.

But, as a rule, the fuel used is not of the highest quality, and filters are rarely changed. Therefore, the injectors in modern diesel engines hardly last 150 thousand km. Then they become dirty and begin to dose fuel incorrectly. To fix this, you will have to at least mechanically clean them of deposits and dirt. It is better not to put this procedure on the back burner, but to entrust the work to people who understand this.

Therefore, fill in high-quality fuel and do maintenance on time. High-quality, timely car maintenance will help you avoid unpleasant breakdowns in the future.

How to clean the injectors yourself without removing them from the engine

During the diagnostic process, a common cause of unstable engine operation is that the injection nozzles are clogged. There are several ways to clean injectors, among which mechanical, ultrasonic or cleaning using special chemical compounds can be used.

In some cases, pouring a special injector cleaner additive into the fuel tank is enough to normalize the operation of the entire system. It is also recommended to rev the engine to high speeds at certain intervals and accelerate the car to 110-130 km/h. on flat sections of the path. In this mode you need to drive 10-20 kilometers. Continuous operation of the injectors under load allows for so-called self-cleaning.

Cleaning the injector should be done as a preventive measure, and not after signs of malfunction appear. If the car is operated in city driving mode on fuel of questionable quality, then the interval of preventive measures should be reduced in relation to individual operating conditions.

When and why you need to remove fuel injectors from the engine. Removing injectors on gasoline and diesel engines: features of the dismantling process.

Cleaning a car injector without removing the injectors. Methods for cleaning injectors with removal on a cavitation stand. Ultrasonic and hydrodynamic cavitation.

Malfunctions of diesel injectors, checking and self-identification of problems. Cleaning diesel engine injector nozzles, regulating injection pressure.

Common diesel engine malfunctions and diagnostics of units of this type. Checking the fuel system of a diesel engine, useful tips.

Operating principle and distinctive features of gas injectors. Basic parameters when choosing nozzles for gas equipment 4. Which gas injectors are best to buy.

Features of operation and causes of malfunctions of diesel injectors. How to independently remove, troubleshoot, disassemble and repair diesel engine injectors.

How to clean an injector

Of all injector failures, 60% of malfunctions occur due to its clogging - it begins to pour into the cylinder. To combat such a common problem, we have come up with several ways to clean injectors.

We list those that can be implemented in a garage:

Cleaning injection elements using an ultrasonic unit (ultrasonic washing) . This method, based on the cavitation effect, is quite labor-intensive and requires special equipment. An ultrasonic bath is used in which the nozzles pouring into the cylinder are washed repeatedly. This cleaning results in good atomization.
Flushing the injector without removing it . It is produced using cleaning additives that are added to the fuel tank. This additive normalizes the operation of the entire engine, including the injection elements that are poured into the cylinder. There is a very large selection of such cleaning products on sale today.

Which of these methods is better? There is still disagreement on this matter. Objectively, it can be noted that ultrasonic washing is most often used for serious problems with the engine (for example, its unclear operation). Flushing injectors with additives, on the contrary, is more effective as part of preventative engine cleaning. In this case, it copes well with carbon deposits that form on the valves. However, the contaminated injector that pours into the cylinder is cleaned superficially using this method. Additives may not be able to eliminate deeper stages of clogging. Moreover, cleaning is done blindly: it will not be possible to target the problem area. Therefore, when it is necessary to check in detail and determine the throughput of sensors, they mainly resort to ultrasonic treatment. It is produced in specialized car services that have the appropriate software for calculations.

Of course, a better cleaning method in an ultrasonic bath will cost 2-3 times more than simple liquid treatment. But here lies another danger. Worn and faulty injectors pouring into the cylinders can be completely damaged by cavitation, as a result of which these elements lose their tightness.

Cleaning injectors on a stand

One of the most popular methods is to clean the injectors on a stand; this method can be implemented independently, or you can contact a car service center. The difficulty lies not only in securing the injectors to the stand, but also in implementing a pulse controller that will supply current to the injectors intermittently. The principle of operation of the stand is simple, nozzles are installed in it, washing liquid is also poured in and the injector is cleaned, during which you can control the spray quality of each nozzle and its performance. The operation is carried out until the nozzles produce the same torch and spray the same amount of liquid over a certain period of time.

A washing stand will allow you to assess the condition of the injectors; you can do it yourself or contact a specialized service.

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