Why is there a check on the dashboard. Check Engine indicator: causes of operation and how to eliminate them. Troubleshooting methods

It is common knowledge that modern cars have gone far from their predecessors, not only in terms of design and comfort, but also in terms of electronics.

The latter factor can hardly be considered an advantage in terms of reliability, but the fact is a fact, and the modern car enthusiast has to put up with it. However, the injection system in power units, which came to replace the traditional carburetor for the sake of ecology, also has a significant convenience - a self-diagnosis system, thanks to which you can find out about the occurrence of engine malfunctions.

On most vehicles, the activation of this system is characterized by the inclusion of the Check Engine indicator on the instrument panel. We will talk about what this system is and from what the indicator lights up in this publication.

Check Engine translation

The indicator with the inscription Check Engine, which in translation from English into Russian means "Check the engine", is designed to signal a possible malfunction in the power unit of the car.

It is displayed if the electronic engine control unit (ECU) has detected an error in the operation of one of the components and assemblies. In order to better understand how this happens, you should briefly dwell on the operation of the entire self-diagnosis system of modern cars.

So, the auto self-diagnosis system includes the following components:

• electronic sensors of the most important elements of the fuel injection system and the exhaust system;

• an ignition control unit that processes information from sensors and regulates the fuel supply in accordance with the received data;

• an emergency display system that notifies the driver of possible problems in the operation of certain units detected by the sensors (it is it, in fact, that lights the "Check" on the dashboard).

Thus, a lit Check Engine can mean, in theory, any malfunction or failure of the sensor.

As a matter of fact, the owners of cars without an on-board computer are faced with just such a situation - the car, through the indicator, informs its owner about the problem, however, it is not possible to find out how serious it is without connecting a diagnostic scanner.

Such a scanner allows you to access the memory of the electronic control unit and read the error code, according to which you can determine the cause of the malfunction with high accuracy.

I must say that many cars with an on-board computer also have this feature, which is certainly much more convenient.

Engine malfunction light comes on - possible causes

Reasons for the Check Engine light bulb to work dashboard there are quite a few. Let's try to tell about them in decreasing order of probability:

• Poor fuel quality (at the same time, the purity of the exhaust is disturbed, which leads to malfunctions of the lambda probe and the output of a warning signal).

• Failure of one or more sensors.

• Violation of the composition of the fuel mixture due to the failure of individual components of the system.

• Failure in electronics.

• Clogged nozzles.

• Disruption of fuel supply to the engine.

• Mechanical faults in the power unit.

Video - Chek lit engine malfunction:

As you can see, serious engine malfunctions associated with mechanical failure of components and assemblies is far from the main reason for the appearance of an alarm signal.

What to do if the CHECK of engine malfunction is lit

In the event that Check Engine caught fire, you should first of all determine the severity of the breakdown. This requires:

• Observe the "behavior" of the vehicle and determine if the malfunction affects the operation of the power unit. In particular, pay attention to the stability of its operation at idle, traction, etc. That is, to understand whether the operation of the motor has changed since the appearance of the signal.

• If the car is equipped with an on-board computer, view the error code, and then correlate it with the code map, which can be found in the literature on the repair of your car or on the Internet. This method, in fact, will allow you to determine the problem with a high degree of accuracy.

• If there is no on-board computer in the car, you can try to throw off the burning "Check" yourself. After all, often the cause of its appearance can be a malfunction of the software or electrical system. To do this, open the hood and disconnect the battery terminal for 10 minutes, completely de-energizing the vehicle. There is a possibility that when you reconnect the terminal and start the engine, the list of temporary errors in the ECU will be reset and the alarm will disappear.

• In the event that there are malfunctions in the operation of the motor, and the "Check" itself does not disappear after the power is turned off, it makes sense to diagnose the motor using an external scanner under service conditions. Wizards will "take" readings from the ECU and will be able to determine the error code. This procedure can be performed independently, but for its implementation you will need a service scanner or a special cable to connect the PC to the car's service connector, as well as specialized software. Since both options are quite expensive, such a purchase is justified only if you plan to do diagnostics professionally. Buying such equipment for personal use is unlikely to be economically justified.

It is worth telling about one more feature. The fact is that the Check Engine warning lamp may not always be on constantly. It is not uncommon for the car owner to notice that Check Engine lights up on the dashboard and goes out. Such "floating" faults are often indicative.

Video - what you can try to do if the CHECK of engine malfunction on the VAZ is on:

If you notice such "symptoms", it makes sense to change the gas station and observe the further "behavior" of the indicator. With a high degree of probability, the lamp will stop lighting up. In addition, when refueling with fresh fuel, use the above advice and de-energize the vehicle for ten minutes. This procedure will erase temporary errors from the memory of the vehicle's central engine control unit.

The appearance of an engine malfunction icon on a number of car models also occurs for some reasons that are characteristic of a car of this brand.

In particular, the fact is known that Check Engine lights up on cars Chevrolet lanos (Zaz Chance) almost immediately after purchase, on a run of 10-15 thousand kilometers. This nuance was not associated with any technical malfunctions and was eliminated by flashing the engine control unit. In fact, it was just a factory defect in the software.

conclusions

As you can see, the appearance of the Check Engine icon does not always indicate a dangerous breakdown. Nevertheless, the factory instructions of car manufacturers when the alarm is triggered unambiguously recommend carrying out the most prompt diagnostics and prohibit the operation vehicle before identifying the cause of the breakdown.

In practice, these tips should really be heeded, and this is due to the fact that the signaling device can inform both about a very simple malfunction that does not affect traffic safety, and about serious mechanical failures, in which the further use of the car is impossible.

Engine operation in modern cars controls an electronic controller (ECU), which receives information from a variety of sensors. In the event of a malfunction, the system activates the "Check engine" warning indicator on the instrument panel. Many drivers do not know what to do in a situation when the engine malfunction light comes on suddenly and for no apparent reason.

Why does the engine malfunction check light up?

A set of service programs is installed in the memory of the electronic unit (like an operating system on a home computer), with the help of which the ECU controls the operating modes of the motor. If the readings of any sensor differ from the norm, the controller memorizes the malfunction code and turns on the "Check engine" warning signal.

WATCH THE VIDEO

Most often, if the check of an engine malfunction is lit, then this means a failure of units or control devices of the following car systems:

In the fuel system: incorrect operation of injectors, malfunction of the fuel pump, adsorber, as well as leakage of the tank;

In the ignition system: unstable operation of spark plugs, faults in high-voltage wires and ignition distributor;

In the exhaust gas system: malfunction of the oxygen sensor, breakdown of the catalytic converter;

In the engine management system: malfunctions of the mass air flow sensor, knock sensor, idle speed regulator and other devices.

Cars equipped with an on-board computer with a self-diagnosis function have the ability to display the decoding of error codes on the screen. For other models, it is possible to determine why the check engin caught fire only using a laptop with special software, which is connected to the diagnostic connector via a compatible cable.

If the check lights up when starting on a cold engine

If when the ignition is turned on, there is no characteristic sound pumping fuel, and the engine icon lights up on the panel, then, most likely, the relay supplying power to the gas pump is faulty.

The exact installation location of this unit depends on the specific machine model and may be in the immediate vicinity of the fuel injection control unit or near the fuse box. The reasons for the failure of the relay can be both a malfunction of the device itself and the failure of the fuse protecting it.

A faulty fuel pump relay must be replaced with a new one, and if the fuse blows, it is imperative to determine and eliminate the cause of this problem, since possible short circuits in the wiring can lead to a car fire.

If there are problems with starting, the cold engine is unstable, it is likely that the fuel injectors are clogged or their wiring is faulty. To eliminate the problem, you need to flush the injection device, and repair the damage in the electrical control circuits.

The reason that the check signal is on after starting the engine may be a malfunction of the device for absorbing gasoline vapors - an adsorber.

This happens if the absorbing element (activated carbon) becomes unusable or the control solenoid valve fails.

Many car owners remove the spent adsorber due to the high cost of a new part. In this case, it is imperative to rewrite the firmware of the control unit in order to avoid the constant appearance of an error in the system.

Often the warning indicator lights up without a malfunction in the motor due to elementary carelessness. Filler plug, poorly tightened in a hurry fuel tank reduces the pressure in the gas lines due to the passage of air. This leads to increased consumption gasoline, which the ECU evaluates as a malfunction and then the check lamp turns on on the panel.

Another cause could be a defective air flow sensor. To ensure the optimal composition of the fuel mixture, the control unit monitors air consumption using the readings of the mass air flow sensor (MAF). With an irregular replacement of the air filter, the working element of the DRMV is clogged with dust particles, which leads to a distortion of its readings.

In such a situation, the ECU switches to calculating the air consumed by the engine by indirect methods and warns the driver about the malfunction through the included "Check". Also, if the mass air flow sensor fails, the engine does not start well at negative ambient temperatures.

Replacing the air flow sensor is quite simple, but the cost of the part itself, depending on the make and model of the car, can reach 10-15 thousand rubles. Therefore, it is better not to skimp on routine maintenance of the machine and timely purchase and install a high-quality air purification filter.

The control of the occurrence of knocking during the combustion of gasoline in the cylinders is carried out using a knock sensor. In the absence of information or a low signal from the sensor, the ECU sends an error message to the dashboard.

Structurally, the sensor consists of a piezoelectric element and a resistor, therefore it cannot be repaired and is replaced as an assembly.

The idle speed regulator (IAC) is responsible for setting and maintaining the required speed in different modes of engine operation. The regulator opens and closes specially the hole in the branch pipe of the throttle unit for dosing air. As a result, the car can start moving immediately after starting the engine without long warm-up.

Unstable engine idling and an illuminated engine fault signal indicate a breakdown of the IAC and the need to replace it.

The check signal went off on the move, the engine troit and runs intermittently

Normal engine operation is impossible without stable ignition of the fuel mixture. If the "Check engine" lights up on an unstable engine, it may mean that there is no spark or misfire in the cylinders due to the following faults:

contamination or failure of spark plugs;

incorrect gap on the electrodes of the candles;

breakdown of insulation or violation of contacts of high-voltage wires;

breakdown of the ignition coil.

Repair work consists of cleaning the spark plugs and setting the correct gap. If the candles have worked for a long time (over 100 thousand kilometers) or have visible defects, they should be replaced with new ones. In addition, even fresh spark plugs can fail due to the use of low-quality gasoline. You also need to check the high-voltage wires for damage, make sure that sparking is normal, and also measure the resistance at the coil terminals.

There are frequent cases when the check still burns after replacing parts of the ignition system. If the installed spare parts are probably in good working order, then you need to erase the error from the computer's memory or wait until it disappears automatically after a certain interval (usually from 150 to 300 kilometers).

The "Check engine" signal is periodically turned on, the engine is not picking up speed well

If the check lights up while driving, and the engine power has significantly decreased, this may be caused by malfunctions in the exhaust system.

In the exhaust system, the control unit monitors the operating mode of the oxygen sensor (lambda probe) installed on the exhaust manifold and also evaluates the condition of the exhaust catalyst.

The malfunction of the lambda sensor can be judged by the significantly increased consumption of gasoline, the suspended content of carbon dioxide in the exhaust, as well as by the decrease in engine power. Modern machines have several of these sensors, so you either have to check them one at a time or use an error scanner.

Also, a serious drop in power is a characteristic symptom of a malfunctioning exhaust gas purification catalyst. In such a situation, besides the fact that the check of the engine caught fire, the car begins to react very sluggishly to pressing the gas pedal. Most often, catalyst breakdown is caused by a malfunction of the oxygen sensor and untimely replacement of candles. In order not to bring the situation to the costly replacement of the collector, it is necessary to observe the scheduled replacement time for the glow plugs.

The warning "Check the engine" turns on, the machine does not pull, the heating of the engine increases

This problem is caused by a malfunction of the cooling system. First of all, you should ventilate the thermostat, it may have jammed on a small circle, and the hot antifreeze stopped circulating through the radiator.

Another option is the failure of the cooling fan or its control electrical system. In turbocharged models, when the engine overheats, the turbine is automatically turned off, which leads to a sharp drop in power and a decrease in traction characteristics.

Ultimately, a stuck thermostat can cause the coolant to boil, often resulting in hose breakage and system leakage.

Also, the problem may be a malfunction of the temperature sensor or poor contact on its connector, which causes a distorted signal to the ECU.

Operation of the lamp check after a car wash

Sooner or later, every car owner has to wash the power unit. This may be due to the leakage of oil or other operating fluids, the deposition of dust and dirt on a wet engine, or it may be required after repair work.

If you carry out preliminary protection of the components from moisture ingress carelessly or overdo it with a high pressure washer, then after switching on the engine troit and stalls, and the "Check engine" signal is turned on on the dashboard.

These problems are most likely associated with a malfunction of the car's electrical system: unreliable contacts of high-voltage wires, ignition coils and other electronic units. There are cases when the pressure of water knocked loose plugs from the connectors of the control sensors.

Eliminate the malfunction by checking and thoroughly drying all connectors in the engine compartment. For added reliability, a moisture-displacing electrical contact lubricant can be applied in suspicious locations.

WATCH THE VIDEO

In conclusion, it should be noted that the triggering of the "Check engine" signal always means that there is some problem. If the check is on, but the engine is running normally, the driver still needs to determine the cause of the warning light and eliminate it as soon as possible.

Which dashboard icon scares the Renault owner the most? That's right, Check Engine. Let's try to figure out why the on-board computer detects an error in the engine and what to do about it.

Indicator Check and its purpose

The engine icon, Check Engine, which drivers often call a "check", normally lights up only when the engine is started - and goes out a few seconds later, after the electronics checks that the systems are ready for operation. The indicator literally translates as "check the engine".

If the "check" does not go out or lights up while driving with the engine running, it reports that a failure has occurred in the operation of the motor and its electronic systems.

To find out the cause of the problem, you need to connect the Renault on-board computer via a special cable to the computer and carry out diagnostics - reading engine errors.

Why does the engine check light up?

A lit Check Engine light indicates a variety of engine problems. Most often, Renault owners are faced with such ones as:

• poor fuel quality / leaking fuel tank
• the fuel pump is broken, the fuel filter is clogged
• insufficient level engine oil
• faulty spark plugs
• the lambda probe is out of order
• the mass air flow sensor DMRV is out of order
• the exhaust gas catalyst is out of order

Check Engine on fire - what to do

As soon as the Renault owner sees a "check" on his dashboard while the car is in motion, he must stop as quickly as possible, and also listen to the engine.

• If no suspicious sounds are found, you can start inspecting the car.
• If, at the same time as the Check Engine lights up, you hear noise, hum, knocking and other extraneous sounds under the hood, the engine troit and loses power - stop as soon as possible and call a tow truck. Attempting to keep driving in this case will result in engine damage.

In any case, the appearance of the "check" indicator should be taken very carefully. Disconnecting the battery or throwing off the terminal so that the icon goes out, and continue driving is not an option. It is necessary to understand the essence of the problem, replace the failed elements and sensors, and not write off everything on "electronics failures".

However, experienced owners can perform a number of diagnostics and even fix them on their own.

What you need to check if the "check" on Renault lights up

• It is worth checking first, is the gas tank cap tightly closed?... If the "check" caught fire immediately after refueling, it may be to blame poor quality fuel... In this case, you need to completely drain the bad gasoline or diesel fuel from the gas tank and refuel with another, quality fuel... If the cover is not tightened enough or is cracked, the indicator will light up too.
• Open the hood and inspect the engine for oil stains and damage? Then remove the dipstick and wait until the engine has cooled down, check oil level, top up if necessary.
• The main reason why the "check" lights up on petrol Renault - failure of the ECM system elements - spark plugs, coils, high-voltage wires, sensors - especially the mass air flow sensor and lambda probe. Therefore, open the hood, carefully inspect the candles, clean the carbon deposits from them, or better - replace them, and the whole set is complete. We wrote about how to independently check ignition coils on Renault. Separate attention should be paid to the insulation of the wiring.
• It is better to entrust the diagnosis of sensors to professionals. Oxygen sensor (lambda probe) over time it becomes covered with oily soot, and cleaning will not help here - the sensor must be changed.
• DMRV It "measures" the amount of air that enters the combustion chamber and helps the engine "prepare" the correct mixture. If it fails, the engine runs unstable, troit, fuel consumption increases, the "check" lights up - all because of a poor or too rich fuel mixture. A broken mass air flow sensor must be replaced with a new one. And in order for the DMRV to work correctly, do not forget about replacing the air filter.
• In diesel "Renault" the Check Engine indicator can report fuel system malfunctions - failure of nozzles or their nozzles, breakdown or corrosion of parts of the injection pump. The diagnostics and troubleshooting of Renault high-precision diesel fuel equipment should be entrusted to professionals.
• Also, the "check" may burn due to a failed fuel pump and clogged with deposits fuel filter... To prevent such a problem, never drive with an empty tank, and on diesel Renault, change the filter before cold weather every year.
• Finally, the cause of the Check Engine light problem is worth looking at malfunction of the exhaust gas catalyst. The catalyst cleans the diesel engine exhaust, and when it gets clogged with dirt itself, the engine power drops, the "check" lights up. The problem is typical for Renault with impressive mileage. The solution is to replace the catalyst, but due to the high cost, car owners simply cut it out, replacing it with a flame arrester.

We wrote about why the ABS icon appears on the Renault dashboard

Hello everyone! Today, under the heading "", we will talk about the "scary" indicator called Check Engine. Yes, I agree, the topic is hackneyed, except that the lazy one did not write about Check Engine on his website, but nevertheless, there is a problem and it must be solved, and so that you, dear readers, do not have to wander around the Internet for a long time, we will give you all the necessary information about this error, as they say, is on the tray. Go!

What is Check Engine? Literally, Check Engine is check the engine. But why does such a harmless phrase cause so much emotion and fear? And the thing is that this seemingly harmless inscription that appears on the dashboard can mean both the "death" of the power unit, and a banal necessity or high-voltage wires. It is clear that every car owner, having seen this yellow inscription, begins, as they say, to wind himself up and prepare for the worst, well, provided that he is not some kind of "naught" or a convinced optimist.

Initially, "Check Engine" monitored the work of the carburetor, and its appearance was interpreted only one at a time - problems with the "carb". However, over time, other problems associated with the engine were tied to this responsibility, after which it became much more difficult to interpret the lit Check Engine light. It detects a malfunction in the engine control unit (ECU), guided by certain algorithms.

We can say that we figured out the meaning, now you know what is "Check Engine" and how dangerous it is. Now let's figure out in what cases you can see this inscription, or rather, how such an error can be caused.

So, modern Check Engines can detect malfunctions of the fuel system, the ignition system, all kinds of sensors and not only ... Finding out why the Check Engine is burning without special equipment is quite difficult, although possible. For example, you can use the so-called "poke method", which involves the replacement of parts one by one, which may be related to this error. The method, of course, is working, but if the problem is trivial, say, a loosely closed gas tank lid, and often it is it that can cause this inscription to appear on the dashboard, and you replaced candles, BB wires and several sensors, then we can conclude that the method quite expensive and ineffective. It will be much cheaper to turn to specialists who, with the help of a special device, in a few minutes determine "where the legs grow from" and will accurately indicate the malfunction.

What to do if the Check Engine message appears?

To begin with, it will not be superfluous to understand when the appearance of the "Check" is the norm, and when not. In a working engine, the Check Engine indicator should appear as soon as you insert the key into the ignition. After you have turned it to start the engine, the inscription will remain on for several seconds, after which it should disappear. In these couple of seconds, the ECU analyzes the operation of the engine and all systems as a whole, that is, the engine self-diagnostics occurs. If all systems are normal, the inscription Check Engine should disappear, if there are remarks or malfunctions, the light will remain on.

Consider another situation where the Check Engine lights up while driving or does not go out after starting. In such cases, the error indicates a malfunction of the power unit and requires urgent intervention. The problem, as I said above, can be trivial, for example, the tanker did not close the tank cap tightly, resulting in the problem of insufficient pressure in the fuel system. In this case, you can simply stop and close the lid more tightly and wait for the error to disappear. Also, do not treat the appearance of such an inscription too lightly, the problem can be quite serious, therefore, as soon as possible, I recommend checking the reason for the appearance of the inscription at the service station.

Check Engine is on - causes and remedies

1. Let's start small. If during the ride, for no reason at all, the Check Engine caught fire, while it works correctly (without extraneous noise, jerks, and other anomalies), we can assume that the problem may be related to. This can be said to be the simplest thing that can be checked without difficulty and the need to call in at the service station. Stop the car and check the engine oil level, if it is too low, add oil, if this is not possible, do not continue driving, it is better to leave the car in the parking lot and buy oil at the nearest auto shop. If the engine oil level is in the range between the "MIN" and "MAX" marks, although it needs to be added, you can continue driving, but add oil to the level as soon as possible. After you have added oil, after a while (individually for each car, some in an hour, others every other day), the error should disappear. If Check Engine is on and does not disappear, you need to continue troubleshooting, you can alone, but better at the service station.
2. The second reason is. Listen to the work of the engine if you notice that the work is uneven, the motor is "troit" or, it can be assumed that the reason for the "Check" lies in candles or high-voltage wires.

From personal experience ... Once I was offered to wash the engine as a bonus, after replacing the timing belt, which I reluctantly agreed. As I was not persuaded not to wrap the sensors and wiring in cellophane by the frivolous service station employees, I did it, but as it turned out later, it did not help. After washing, the engine, of course, shone, seemed absolutely clean and new, but after I left the walls of the service station, something incredible began to happen to the car. An attempt to overtake a truck for me almost turned into a fatal accident: pressing the gas pedal "to the floor", instead of the dynamics, I got a failure, the engine "choked and troilus", after which the Check Engine caught fire and the engine stalled. You understand, shock, square eyes, a lot of questions and a frightening Check Engine inscription. When I came to, I called the service, a specialist was sent to me who diagnosed the explosive wires and candles flooded with water. After purging and drying, the Check disappeared, and the motor began to work as before. As you can see, a banal engine wash can cause a lot of trouble, and also cause an inscription on the "tidy" Check Engine.

1. Low fuel level. Oddly enough, an empty tank can also cause the Check Engine to appear. When there is very little fuel in the tank, the pressure in the fuel system drops, and the gas pump may begin to suck in air, as a result - an error.

Also from personal experience. The gas station at which I constantly refuel, which I trust, is at a distance of 20-30 km from me, I do not go there specifically, just when I am in those parts I call in and refuel. Once I reached the point where the fuel level dropped to the lowest mark, while the emergency fuel light was not yet on, I did not see how it was lit and how it looked. On the way to the gas station, I accidentally noticed that some new icon was lit on the panel. No, I'm not a novice driver who does not distinguish a Check from an Airbag, it is just that sometimes ESP can be lit there, sometimes the badge of unfastened passengers, etc. But what was my surprise when, instead of harmless indicators, I found Check Engine there. As expected, I stopped, turned off the engine and waited a few minutes in order to decide how I would proceed. I checked the level of all liquids, checked the wiring and the tight connections of the sensors to which I had access. Then I started the engine again, but the Check was still burning ... There was not much left before refueling, so I decided to refuel and go to the service station to find out the reasons. Then I had no idea that it was the low fuel level that could cause this error to appear, or rather, I heard about it, but did not take it into account. After refueling, the error still did not disappear, so it was decided to make a reset. If you do not have specials. equipment, then the maximum you can do is to throw off the "-" terminal, which I actually did. After several minutes I put the terminal back in place, started the engine and lo and behold - Check disappeared! Joy knew no bounds, but after this incident I began to look more closely at the icons on the panel. And for myself, I concluded that driving with a half-empty tank is not only harmful to the tank and, but also fraught with the appearance of this unpleasant inscription on the dashboard.

List of reasons that can also cause Check Engine

1. Low quality fuel. If you are pouring anything into the tank, be prepared to see an error in the form of a "Check". The problem is solved by draining "kaki" and refueling with normal fuel.
2. Tank cap. Check whether the filler cap is tightly tightened, due to a loose fit, air may leak, after which the fuel consumption will increase and the control unit will give an error in the form of "Check Engine".
3. The Lambda probe. A defective oxygen sensor often causes the Check Engine to catch fire. Check the oxygen sensor, if it is faulty - replace it with a new one.
4. Mass air flow sensor (mass air flow sensor) can cause the inscription "Check Engine" to appear on the dashboard. To see if the cause is there, you need to check the sensor using a multimeter.
5. Spark plugs and BB wires. As I said above, problems with spark plugs and high-voltage wires can affect the operation of the engine, after which the ECU diagnoses the malfunction and notifies you accordingly, that is, "Check Engine" appears. How to solve the problem? Elementary, check the candles and BB wires, remember when they were last changed, assess the condition and, if necessary, replace them.
6. Ignition coil. If you suspect that the coil is not in order or may be related to the error that has appeared, check the coil, make sure that there is a spark, then make sure that there is resistance at the terminals of the coil, while the spread should not be more than 1-4 and 2-3 ...
7. Problems with the catalyst. We'll have to remove the muffler and check the condition. If it turns out that the catalyst is "dead" - you will have to change. This breakdown is quite rare and, as a rule, typical of old cars.
8. Injectors. These important details can also cause "Check Engine" under certain circumstances, especially considering the quality of the fuel that we fill with you.
9. and a gasoline pump. A clogged fuel filter can cause a pressure violation in the fuel system, the ECU will detect this failure and the Check Engine will light up. The same applies to the fuel pump, if it does not work properly or is faulty, you can see the "Check". In principle, if the problem is really connected with the pump, then before the error lights up, you will feel unstable engine operation, deterioration of dynamics, etc. Solution to the problem: check the pressure in the fuel rail, make sure that the coarse mesh and the fuel filter are in normal, if necessary perform a complex replacement.

If the above steps did not lead to anything and you still do not know why is Check Engine lit, I advise you to contact a specialist to eliminate the error and its cause. Any delay can cost you and your engine dearly.

The "Check Engine" icon on the dashboard signals the owner that a diesel engine malfunction has occurred. Actually, that's why it is necessary to "check the engine".

There are many reasons why the "Check Engine" warning comes on. And it is not easy to understand them, especially for a non-specialist.

So, the "check" can light up in case of any malfunctions in the ignition system and the fuel supply system, in case of malfunctions in the timing phases, when the engine detonates, in case of failure of various sensors, with a lack of oil in the engine or gearbox, and even when refueling low-quality fuel.

Accordingly, the solution to the problem will be different - from replacing inexpensive elements to major repairs.

"Check Engine" lit up - what to do

In any case, if the owner sees “Check Engine” on the dashboard while the car is in motion (normally this lamp lights up after turning on the ignition and goes out after a couple of seconds), you need to listen to the motor, then stop and inspect the engine for oil stains and visible damage.

If, in addition to the icon, there are no failures in the operation of the internal combustion engine, you can go to the service and diagnose the problem.

But if strange sounds appeared along with the "check" - knock, hum, creak from engine compartment, or the engine "troit" and noticeably loses power, you need to stop as quickly as possible and call a tow truck.

Further operation of the machine with a flashing "Check Engine" in motion and signs of engine damage may end in disaster.

Why "Check Engine" on a diesel engine can burn

In gasoline engines, the reasons why the "check" lights up are mainly related to the ECM system - it is worth diagnosing spark plugs and ignition coils, and also high-voltage wires and numerous sensors - camshaft position, speed, mass air flow sensor, oxygen, etc.

In diesel engines the reasons that lead to the "Check Engine" warning (with the exception of ECM system problems) are similar: incorrect operation of the sensors, problems with the exhaust gas catalyst, fuel system malfunctions. Let's consider the probable problems in more detail.

bad fuel

Often, residents of the CIS are faced with the fact that the "check" lights up after a recent refueling of the car. If at the same time there is a loss of power, the reason may lie precisely in the quality of fuel.

Incorrectly selected, bad diesel fuel can cause knocking in the engine, disrupt the normal combustion process. The electronic engine control unit records these changes - and gives an error.

To solve the problem, it is often enough just to dilute the already filled fuel with high quality. If everything is done correctly, after a couple of kilometers of run, the "Check Engine" will go out by itself.

In severe cases, the fuel will have to be drained completely, and the fuel supply system will have to be flushed. If after that the "check" does not go out, the error will have to be reset through the program.

tightness of the fuel system

The "Check Engine" warning is not always associated with serious malfunctions. Sometimes such an indicator lights up when too little or too much fuel enters the engine for some reason.

Therefore, the first step that the owner should take is check the tightness of the fuel tank closure - its cover may be cracked or loose. Such a banal reason often explains the appearance of a "check" on the dashboard.

If the inspection shows cracks in the lid, it must be urgently replaced. If the lid is unscrewed, you just need to tighten it and drive a couple of kilometers for the check to go out.

the oxygen sensor (lambda probe) is out of order

The oxygen sensor is involved in adjusting the proportions of the fuel mixture. It collects data on how much oxygen is contained in the exhaust gases and is transmitted to the engine management system. Depending on this data, the ECU decides whether to enrich or lean the fuel mixture on gasoline engines.

In diesel engines, the lambda probe together with a mass air flow sensor (MAF) helps to accurately determine the degree of exhaust gas recirculation for each operating mode.

That is, the purpose of the oxygen sensor is to transmit accurate data to the engine control system in order to make it work more economical and environmentally friendly. In modern cars, 2-4 oxygen sensors are installed.

Over time, the lambda probe becomes covered with a layer of used engine oil and begins to transmit erroneous data to the engine ECU. As a result, too much or too little fuel enters the chamber, which leads to malfunction.

The solution to the problem is to replace the faulty oxygen sensor, and it is better not to postpone it, because a faulty lambda probe can damage the catalyst.

the mass air flow sensor is out of order

Mass air flow sensor together with an oxygen sensor participates in fuel metering when preparing an air-fuel mixture.

When the DMRV fails, the proportion of the formation of the fuel mixture is violated, hence the malfunctioning of the diesel engine, difficulties with cold starting, loss of power and an increase in diesel fuel consumption.

Moreover, the breakdown of the sensor can be caused by a violation of the rules for replacing the air filter.

The faulty sensor must be replaced, otherwise the problems in the operation of the motor will not be eliminated, and the "Check Engine" warning will remain on on the instrument panel.

breakdown of the exhaust gas catalyst

The catalyst cleans the exhaust and reduces the amount of nitrogen oxide that diesel engine during its operation, it emits into the atmosphere.

The catalyst may break due to a failed lambda probe, as described above. Overheating, the catalyst housing bursts, and a "check" appears on the dashboard.

You cannot drive with an inoperative catalyst - the car will lose dynamics and consume more fuel.

Due to the fact that the repair of the part is complicated and expensive, many car owners in such a situation simply cut out the catalyst, installing a flame arrester instead.

engine overheating / oil starvation

If "Check Engine" lights up in the summer, and even in a traffic jam - it's bad. The reason is to look for overheating of the motor.

And if its temperature is normal, and no antifreeze leaks were found, it is worth checking the engine oil level and its condition.

If the oil is in order, you can start the internal combustion engine and listen to the uniformity of its operation. If the oil is below the minimum level on the dipstick and looks suspicious, it is better to go to the service for diagnostics, and not on your own.