Why is the engine malfunction light on. Check engine light up - Possible causes

»Check engine lit up - what to do?

Check engine lights up - we understand the reasons for the car malfunction

Many owners of light vehicles for the time being do not pay attention to devices and bulbs that do not give "distress signals". The owners of cool foreign cars stuffed with electronics, which means Check Engine, do not know.

For us drivers

When the light comes on, best case drivers ask themselves the question: why did it catch fire and what to do?

Indeed, what measures need to be taken when?

1. First, there can be several reasons for the light signal to come on.
2. Secondly, the problem often has to be looked for for a long time and without computer diagnostics not enough.

A little educational program

Most of the cars that have left the factory gates today are equipped with a warning light installed on dashboard - check engine.

An active light indicates what needs to be checked power unit... The control unit has detected a problem and informs you about it.

In the early 1980s, cars were equipped with mini-computers to control the carburetor. Gradually the field of application expanded. Currently, on cars, the "silent controller", which has undergone a serious evolution, monitors:

• behind the composition of the feed mixture,
• fuel consumption,
• speed of the power unit,
• the moment of ignition.
• controls gear shifting in automatic transmission.

Which one is far from complete list control functions can you make a logical conclusion? That's right, there are more than enough reasons for the check light to come on.

Consequently: without certain knowledge and practical skills, it is extremely difficult to identify the cause of the warning light coming on.

So what needs to be done, what action to take? Let's figure it out together!

Check engine caught fire , how to proceed?

Did you know,

that the check engine light comes on is an inconclusive verdict of an engine malfunction?

1. If the Check Engine indicator, when starting the power unit, signals problems and immediately goes out, do not worry. Your engine is not susceptible to "technical diseases", is in good working order and cannot be "treated".
2. When you turn on the engine after the light warning appears, the Check Engine does not turn off for a long time - it's worth considering. There must be problems. They can be large-scale or minor. It is better not to risk it and turn to specialists.

What makes the check engine "blush"?

• If while driving, you notice that the Check Engine light comes on, probable cause there may be an insufficient oil level in the power unit. In this case, it is recommended to stop and, without turning off the engine, open the hood to listen to the operation of the unit. If the motor runs smoothly: there is no grinding noise and extraneous noise or knocking, pay attention to the tightness. You may find smudges on the engine housing. It is recommended to seek advice and resort to the help of service station masters.
• The Check Engine warning light may be related to the spark plugs. Most likely, one of them is out of order (misfire).
• The check is capricious when the fuel is of poor quality, which is often the case when refueling. This problem manifests itself as soon as you leave the gas station.

Consider the options for lighting the Check Engine light and ways to solve problems

About problems and methods of liquidation
	Cause of malfunction	How to fix
1	Low-quality fuel filled.	It is recommended to drain the contents fuel tank and refuel with "normal" gasoline or high-quality diesel fuel.
2	Problems with spark plugs: cracked insulator, gap not adjusted, carbon deposits.	Check, replace if necessary.
3	Failure of the ignition coil.	Check the spark with an ohmmeter. The recommended coil resistance at the output is 1–4, 2–3.
4	The Lambda probe.	Check oxygen sensor. If it fails, it is recommended to replace it.
5	Catalyst.	Functional check required. If necessary.
6	Injector problems.	Verification is required to find out the reason. Clean if necessary.
7	Fuel pump "junk".	Checking the pressure in the rail. The normal state is up to three atmospheres.
8	Fuel filter problems.	Having found a problem, clean the filter, and or completely replace the gas pump.

This is an incomplete list of reasons that influence the Check Engine light on.

You can eliminate the errors that have occurred without using a diagnostic scanner yourself. Experienced drivers eliminate the error in this way. Unscrew the battery terminals. Put them aside, avoiding a short circuit.

Waiting time is not more than 20 minutes. If you connect the battery and start the power unit, you see a reset clock and an extinguished control check Engine light you have completed the task. However, it must be remembered that in this way accumulated errors are removed. The real problems of the power unit will appear on the second day of vehicle operation.

How to check high voltage wires

The check engine light came on

Could it be high voltage wires? Sometimes it happens.

Advice: follow and follow the instructions exactly.

Fill a saucepan with liquid. You can use a regular saucepan. Necessarily made of stainless steel. Add some salt. 1 tablespoon will be enough. Take a megohmmeter by dipping the wires into the water. The ends should be on the surface.

We connect the device to 1 handpiece. We fix it with a clamp. 2 we put the clamp on the container where the wires are left on the surface of the water. If the resistance shows more than 1 megohm - insulation in good condition... In some cases, a value of at least 500 kΩ is allowed. If the indicators are below the critical mark, the wires need to be replaced.

Recommendation: if the methods of self-conducted diagnostics did not give a positive result (the check engine light is still on), specialist intervention is required. And it's urgent! Otherwise, the problems can be massive.

Tips for those on the road

No matter how well you know about cars, but specialists, who are armed with special equipment, understand more about the occurrence of this or that cause of the "alarm signal". Moreover, service station masters have constant practice, and this experience cannot be taken away!

Experts do not advise to take any measures to eliminate the malfunction if you are not confident in your abilities, it is best to call a tow truck and send the car to the nearest station maintenance.

As a rule, for many car manufacturers, the check engine light comes on when engine malfunctions are associated with a violation of injection and deterioration of exhaust, which will greatly affect the environment.

Diagnostic work is the first step towards finding out possible problems... A brief diagnosis will show what influenced the lighting of the light bulb, and the master will outline the essence of what is happening.

When heading to the service station and driving a car, you must take precautions.

• Do not load the power unit
• Try to drive at a constant speed not exceeding 60 km / h.
• Monitor the speed level. Avoid going beyond the 2500 rpm mark.
• Reduce loads. Somehow shut off the air conditioning system and more optional equipment... Refuse for a while from your favorite multimedia system. Switch off electrical devices that do not affect the normal and safe movement of the vehicle.
• Drive smoothly, avoiding sudden acceleration and emergency braking.
• Plan to drive to the service station during daylight hours. At night, the headlights create additional loads on the power unit. You can move at night, subject to increased attention, in compliance with the above conditions.

Habitual driving style is possible after checking the car and recommendations of the workshop specialists.

And further

It should be understood that the check engine light can come on at any minute. This is not a reason for panic, but only a warning about possible malfunctions... It is not recommended to ignore the check engine warning signal. Since the consequences of neglecting the warning devices are fraught with serious consequences.

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The translation of the expression "check engine" in Russian literally sounds like "check the engine". The check icon is on the dashboard of most modern carsmobile phones, but its significance for many remains unclear. Therefore, if this icon is yellow or orange engine icon - appears and does not disappear (or simply blinks), an inexperienced driver has a natural question: "what does this mean?" Next, let's try to find out the reasons why the check engine lit up on the dashboard of your car, as well as how to get rid of it.

Initially, this light let you know about problems with the carburetor, but now that cars are equipped with full-fledged on-board computers, the message may indicate different faults... For example, a check engine error may report about problems with the quality of the air-fuel mixture or ignition faults, as well as much more. Messages can be caused by both minor breakdowns and critical ones.

Thus, when the check engine is on, it is only clear that it has fixed a malfunction in one of the vehicle systems. The complete picture can only be given. Next, we will analyze the main reasons why the check engine light is on, and what needs to be done about it.

TOP 10 reasons why check engine caught fire

1. Fuel filler cap open... Check if it is tightly closed.
2. Bad gasoline... The system can respond to fuel quality. The solution will be to drain the gasoline and fill it with a better one.
3. Oil level... First of all, check its level with a dipstick. Also look for cracks in the block and oil leaks.
4. Problems with the gas pump or a mesh in the tank. Check if the pump runs smoothly and does not make any abnormal sounds.
5. Dirty nozzles... Eliminated.
6. Malfunction of high voltage wires or coils.
7. Spark plug problem... The icon also lights up in case of problems with candles. It is worth checking the performance of the candles and, if necessary.
8. in one of the cylinders.
9. Defective lambda probe... The problem is eliminated only by replacing this node.
10. Broken catalyst... It is also solved by replacing the catalyst.

Only the main reasons and how to solve them are listed here. In fact, there are many more of them. Diagnostics on-board computer, which controls all systems of the car, can give a more complete picture of the current situation.

Chek Engin is not hiding on the dashboard of the Mazz CX-5

Check engine on the panel Peugeot Partner hiding in the left corner

How to remove check engin

Let us dwell in more detail on the steps that must be taken in the first place in order to get rid of the lighted Check Engine indicator. The priority action algorithm will be as follows:

1. Check, is the gas cap closed... The situation is especially relevant if you have just left gas stationand shortly after that the check engin icon lit up. This means that either the tightness of the fuel system is broken due to an insufficiently tightly tightened tank cap, or the quality of the fuel leaves much to be desired.
2. Check the condition of the candles... To do this, unscrew them and visually assess their condition. Very often, it is the candles that cause the Check Engine indicator to activate. In particular, the reason may be that they begin to pass current due to carbon deposits on the electrodes. Such deposits are formed as a result of the high content of metals or other conductive substances in the fuel. Also, an error may occur if the gap between the electrodes on the candle has exceeded the distance of 1.3 mm. In more detail and how to perform it according to their color, we consider separately. You will also find useful information on how to replace them.
3. Oil level. If the check engine icon lights up only when the engine warms up, stop and listen, you may hear extraneous sounds in the engine. Check oil level with a dipstick in the engine, top up if necessary. Also look for oil leaks.
4. If your car is equipped with cleanliness sensors process fluids (engine oil, fuel and so on), then the indicator may light up if the corresponding indicators exceed the permissible norm... The solution is to replace the corresponding filters or completely fluids in case they do not comply with the standards.
5. Resetting the negative terminal from battery (15 ... 20 seconds). After that, the Check Engine lamp should go out, and the clock on the computer should be reset. This method can be relevant in two cases. The first one is a banal "glitch" of the ECU. The second - if a large number of small errors have accumulated in the memory of the electronic unit that have not been cleared. (they are usually caused by the use of low-quality gasoline, the presence of harmful impurities in the fuel-air mixture, moisture on electrical contacts, etc.).

If, after performing the above actions, the Check Engine indicator does not go out, or goes out, but soon lights up again, then this means that the error lies deeper, and to eliminate it, additional detailed diagnostics must be carried out using more serious means.

Check engine is on - what should I do next?

You can try to find out the reason yourself, counting the number of flashes of the "check", and check the technical documentation for the designation of such an error code. For different cars there are different intervals between flashes and different codes by which they are interpreted.

Most of the errors that the indicator tells you about are are not critical... Diagnostics can be performed in two ways - on your own and by visiting a service station. The fact is that in order to obtain information in this case, you need special equipment or, at least, software for a smartphone.

But first of all, you need to find out how the car's behavior changed after the error appeared. This is done in order to determine if it is possible to go with the check engine illuminated on the panel, or it is better not to do this, so as not to aggravate the problem.

Auto behavior	The icon is lit continuously	The check is blinking
There is no change in the behavior of the car	Traffic can continue	Keep moving CAN'T
The machine changed its behavior abruptly: Float turns; Engine vibration appears; The smell of burning is heard; Other changes.	CAN'T keep moving	CAN'T keep moving
Engine power and throttle response remain the same	Can keep moving	Can keep moving
The engine has become less responsive, the speed does not rise above a certain value (engine operation in emergency mode)	Keep moving can	Continue movement CAN'T
No additional warning lights on the dashboard came on.	Can go	Go can
Along with the check engin icon, another indicator lit up: Coolant light; Overheating of the engine; Oil can light; Catalyst icon.	Traffic CAN'T continue	Traffic CAN'T continue

When does engin's check burn?

Finding out the reason why check is on

The error code can be read using a laptop with a special software... The computer is connected via a cable to the computer's ECU and diagnosed. Also, using a laptop, additional external commands can be entered into the control unit or the errors that have appeared can be corrected (reset).

An easier method is to download an ECU communication and analytics program to your Android smartphone (for example, TORQUE, it has free and paid versions). A Bluetooth adapter is connected to the electronic unit, which allows you to read information from the device. If you do not have a laptop or you simply do not want to fool your head by installing additional software, then you can delegate the described procedures to the workshop workers. They have everything necessary equipment and programs.

It must be remembered that every machine (and sometimes every ECU on identical cars, but different years of release) has different error decryption list... Therefore, after receiving information, you must definitely have standard set Diagnostic Trouble Codes (DTCs). You can find it in additional literature on diagnostics or on the Internet (for example, in thematic forums dedicated to your model of car).

Another common reason for injection engines are problems in the operation of the injectors. In particular, the appearance of a significant amount of sediment on them. The solution to this problem is. If problems appear with candles, nozzles, as well as an activated check engine indicator, there may be the following symptoms:

• weak engine thrust;
• high fuel consumption;
• jerks when picking up speed or unstable work motor;
• "Floating" engine idle speed.

The next step is to check the pressure in fuel system... To do this, you need to use a pressure gauge. Standard pressure for most non-tuned cars is 3 atmospheres (kgf / cm2). However, check the data sheet for your car for this information. If the pressure is much lower, then the problem may lie in a faulty gas pump or dirty injectors. If the pressure is constantly low, check the fuel pump. If at first it is normal, but falls shortly after starting the engine, check the injectors. Also pay attention to the mesh in the gas tank.

Also worth check the insulation of high-voltage wires... It is better to do this not visually, but with a tester included in the ohmmeter mode. Minimum value wire insulation should be not less than 0.5 MOhm... Otherwise, the wire must be replaced.

If the Check Engine light comes on after turning the key, and after a few seconds goes out, then this means that the system is conducting self-diagnostics, and there is no reason for concern.

How to get to the service station when Check Engine is on

When driving to a service station, try to observe a gentle driving mode. In particular:

• do not exceed a speed of more than 60 km / h;
• do not exceed engine speed of more than 2500 rpm;
• turn off the air conditioner (stove), multimedia system and other currently unnecessary equipment that creates additional load on the engine;
• avoid abrupt starts and braking, drive smoothly.

You can return to normal driving mode only after diagnostics and elimination of the identified errors.

Instead of a conclusion

Remember that you should not panic when the Check Engine light appears. In most cases, the reasons for its activation are not critical. However, it is necessary to perform the first-priority diagnostics consisting of the 5 steps listed above. Also check if the behavior of the car on the road has changed or if other indicators come on additionally. If you identify minor flaws, you need to correct them. If the Check Engine does not go out after that, then perform additional diagnostics through electronic device... It will give you an error code indicating the cause of the breakdown.

In the 21st century, cars are crammed with electronics and can inform the car enthusiast about any malfunction. Electronics will help identify almost any problem associated with technical part... With the help of various indicators, the car will report a malfunction at an early stage, which will help fix it before it is completely damaged.

Let's take a look: when and why the engine malfunction indicator lights up, how to remove it, and why you need to fix the damage as soon as possible.

Various Check Engine Indicators

CHECK ENGINE - what does it mean

Car enthusiasts know that the indicator yellow light on the dashboard, this is the “Check engine”. It lights up for a few seconds, when the car is started and immediately goes out, this is a test of the electronic diagnostic system for operability. But if, with the engine running, the check caught fire or did not catch fire at all, then you should not panic. In this case, you need to immediately contact the service, or try to scan the error yourself, diagnose, and then solve the problem and erase the error. This signaling device can mean almost everything: on cars of the 90s, he talked about carburetor malfunctions, on modern injection cars, the range of its work has increased significantly. Now "check engine" notifies not only about problems with air-fuel mixture, entering the CPG, but also about problems with ignition, various sensors, with incorrect operation of the automatic transmission, etc. Almost all elements of a modern internal combustion engine are controlled by electronic systems. Very often, the check lights up due to the quality of the gasoline. The problem is that due to bad fuel, deposits and carbon deposits form on the candles, as a result of which sparking worsens, and the car starts to run unevenly, and detonation may become more frequent due to carbon deposits in the combustion chamber. This can be both with an old and a new car, unfortunately no one is immune from this.

To fix the problem, it is enough to fill in high-quality gasoline or diesel fuel and drive a few kilometers, then the lamp will go out by itself. But in some cases, you will have to replace the filter element and flush the entire system from low-quality fuel.

There are other malfunctions due to which the check is burning, for example, a burned-out catalyst or lambda probe gives incorrect readings, even a “check engine” will notify you of problems with the injectors. If the indicator lights up, then start with a visual inspection, such as unscrewing the spark plugs, checking the oil and those. liquids, try to disconnect the terminal from the battery for 30-50 seconds, and then put it back in place, in a situation where the inspection did not give anything, it is recommended to contact the specialists who have connected diagnostic cable immediately recognize the problem, this is the convenience of modern cars.

Diagnostics using specialized equipment costs about 1000-1500 rubles and accurately indicates a breakdown. It also happens that an ordinary failure has occurred in the electronics, in which case the wizard will simply reset the errors, and the check will go out. In any case, do not dismiss this indicator, it will help you cure the malfunction at the initial stage and save you money.

TOP 10 causes of engine error CHECK ENGINE

1) Poor fuel quality or loose fuel filler cap

The most common reason associated with the appearance of the CHECK ENGENE error is a fuel quality problem, to solve it it is recommended to fill up with high-octane fuel at a proven gas station, you should also check the tightness of the fuel filler cap.

2) Breakage of sensors responsible for mixture formation (DMRV, DPDZ, IAC, MAF)

If any of these sensors break down, you can tell by the behavior of the car. It either simply won't start, or it will work very unstable. IN modern car it is quite difficult to identify a broken sensor, but diagnostics at the service station will help you, the wizard will quickly determine and solve the problem, basically everything is by replacing the faulty sensor.

3) Ignition system malfunctions, misfiring (spark plugs, high voltage wires, ignition modules)

If you notice that your engine is tainted, then one of the problems may be misfiring, this can be associated with both spark plugs and ignition modules, while diagnostics show an error. It is worth starting with checking the candles and armored wires, if this does not help, it is better to contact the service station, because the car can be tripled not only because of the problems associated with the ignition of the mixture.

4) Oil level

It is worth checking the amount of oil with a dipstick, where did it go?

There are a lot of options: oil seals, violation of the integrity of the pallet, problems with the oil scraper rings and seals. Having found out the reason for its disappearance, you can quickly eliminate the defect, add oil and continue driving. You cannot operate a car without oil, even to the nearest service station in the absence of lubrication, you will have to drive a tow truck.

5) Air leaks (various vacuum hoses, collector gaskets)

It is quite difficult to detect air leakage, motorists advise to spray wd-40 or soapy water on the joints of the hoses and collectors, if the speed increases or, on the contrary, falls, then the problem has been identified - it is air leakage. It is quite simple to eliminate it even with your own hands, you need to replace the gasket or hose.

6) Problems associated with the flow of fuel (fuel pump, fuel filter, RTD)

This problem is diagnosed instantly, you just need to check the pressure in the fuel rail. Normal pressure for gasoline cars is 2.3 kgf / cm2. If the pressure is lower, it is worth checking the fuel pressure regulator. If you haven't changed for a long time fuel filter, then it is worth replacing it, as well as checking the fuel pump for extraneous sounds.

7) Clogged nozzles

The symptoms of dirty injectors are very often similar to problems with a gas pump and fuel pressure. The engine runs unevenly, there are increased vibrations, and knocking may occur in some operating modes. The solution to the problem is to clean the nozzles or replace them. All this can be done both with your own hands and in a service station.

8) Defective lambda probe

Only diagnostics and reading error codes will help you diagnose a breakdown of this unit. Unfortunately, there is no way to repair the lambda. The problem is treated only by replacing the oxygen sensor. It is better to replace it as soon as possible, because fuel consumption with a faulty lambda increases by about 30%.

9) Problems with the power supply (generator, relay regulator, open circuit)

This malfunction is usually manifested by the presence of two signaling lights: “check engine” and “battery light”. In order to check the generator and the regulator relay, it is enough to check the battery voltage on a running car, it should be about 13.8 volts.

10) ECU error

There may be absolutely no problem. It's just that the electronic control unit turned on. In order to turn off the light bulb, it is enough to remove the terminal from the battery for 30-50 seconds. If after that the light went out when the car was started, then there is no reason for panic, the ECU simply had a “glitch”.

Poor fuel is the main reason for the appearance of this indicator on the dashboard

Resetting or clearing CHECK ENGINE error

Most budget cars have a primitive ECU and to remove errors you need to do a few simple steps:

• Warm up the car to a temperature of about 90 degrees;
• Remove the terminal from the storage battery for 1-2 minutes;
• Then you can start the engine as usual.

Such actions will help to reset the ECU errors. Zeroing causes the bulb to no longer disturb you after starting the engine. This method will help to remove the error if it was caused by the operation of the engine with faulty sensor, or with a disabled sensor, but if the malfunction is not eliminated, then this method will not be useful.

If the error cannot be removed by removing the battery terminal, then you can use a professional diagnostic scanner and remove the errors programmatically. This method is suitable for those who, after fixing the breakdown, the error does not stop burning. To do this, you need to connect diagnostic equipment into a special connector located in the car. Motorists prefer to contact the service station to implement this method, they can print out all engine errors and clearly explain to the motorist the list of necessary repairs.

Also cars after 2000 have a universal OBD2 diagnostic connector. In specialized stores you can buy a universal scanner that connects to your phone using Bluetooth. It also helps diagnose the problem and has an error reset function. This device costs from 500 rubles and is affordable for every motorist, I consider it a necessary item for any car owner.

Operating rules when the engine error light is on

Using a car with a lit CHECK ENGINE indicator will not lead to anything good, perhaps I will reveal a secret, for some cars not only an error is recorded, but also the distance traveled with this problem, so if you drive for a long time with a burning check, the dealer may break the warranty obligations.

First of all, you need to try to reset the ECU yourself, perhaps you have poured low-quality fuel or you just have a “glitch”, if after resetting the signaling device goes out, then you can safely continue driving.

Then you need to independently check all the connectors and the oil level, if your level of training does not allow you to do all the steps described above, then if the oil level is normal, you can safely drive to the nearest service station or dealer, the main thing is not to make sudden accelerations and not give the engine heavy loads in the form of high revs.

1. The oil level is below normal - it is worth using the services of a tow truck, or taking a cable to the nearest service center, it is imperative not only to throw off errors, but also to eliminate the cause of the problem;
2. You are ready to follow the steps described above - try all the options described in the article, perhaps you can fix the problem yourself, this will deprive you of unnecessary costs for the service station.

You should not panic when a Check Engine error appears, very often this light comes on due to minor problems. Try the first steps described above, if they did not help, but the engine power and thrust did not change, try to drive to the nearest service station on your own and solve the problem, also some cars have a self-diagnosis function, error codes can be found on the Internet.

If you have any questions - leave them in the comments below the article. We or our visitors will be happy to answer them

Modern cars are equipped with various electronic components, in particular, recently, almost all cars have an electronic engine control system (abbreviated ECM). This system has a warning indicator, which is located on the instrument cluster, the name of the warning light is Check Engine.

Check Engine Purpose

The "check engine" icon is used to warn the driver about malfunctions in the engine electronics; if a malfunction occurs, it lights up. There are error codes by which a malfunction of sensors or a control unit is determined. If these errors are detected, the engine icon is illuminated.

If the ECM detects no faults, the Check Engine lights up only when the ignition is turned on. When starting the engine, the yellow engine icon should immediately go out and no longer light up until the next engine start. In the presence of errors, the signaling device can behave in different ways:

• Burn constantly;
• Light up only with an increase in speed;
• Flashing intermittently - and the engine malfunction icon may light up randomly or when driving on an uneven road.

Possible malfunctions

Why does the check light up? The engine icon in the instrument panel indicates that the electronic system any glitches have occurred. The following problems most often occur:

• One of the sensors of the electronic system fails;
• Contact is lost in the wiring plugs;
• An open circuit occurs in the wires going to the sensors or the control unit;
• Breakdowns are detected in the control unit itself.

Causes of failures

It's just that malfunctions in the ECM do not appear, they arise for some reason. For example, a check often comes on after refueling low-quality fuel... But even if you merge bad gasoline and then refuel with good fuel, the error is unlikely to disappear, because one of the sensors or injectors fails from low-quality fuel, but the quality of gasoline signal lamp does not define in any way. The motor icon may light up because dirt or water has accumulated on the motor, which are contactors and cause a short. There may be other reasons for the burning check engen badge.

What to do if the "check" of the engine caught fire

17.06.2015

Indicator lights and indicators on the dashboard are the main source of information for the driver. With their help, you can find out the main indicators of the car, identify and eliminate the malfunction in time. If there are no problems, some of the lights come on when the ignition is turned on and go out after the engine is started. But what if the check engine light comes on and stays on even while driving?

Appointment

The task of the indicator is to inform the driver about a malfunction of one of the engine systems. How does everything go as usual? When the ignition is switched on, the electronics are checked. If, after a poll, the ECU has no "complaints" about the power unit, then after a few seconds the lamp stops glowing. If the "check engine" continues to burn after testing or lights up already during the trip, then the owner should think about a trip to a service station and troubleshooting.

What to do?

Please note that a long glowing lamp is a clear sign of a vehicle malfunction. In such a situation, it is necessary to slow down and stop on the side of the road. Listen to how the engine is running, if there are any suspicious noises or knocking. Get out of the car, open the hood and inspect the power assembly for obvious oil leaks, damage to the case, or other problems. If the reason is a leak, then check the oil level, top up and try to reach the nearest car service. If the damage is serious, then the only chance is to stop another car and ask you to tow it to the place of repair.

There are situations when the engine, after the "check engine" lamp comes on, runs smoothly and without interruptions, and the inspection does not give any results. Here, the reason may be the failure of one or more candles. If the indicator comes on a few kilometers after driving to a suspicious gas station, then the reason may be the poor quality of gasoline.

In fact, there are many reasons for the check engine lamp to light up, because a number of indicators from the ignition system converge on it, automatic box gears, carburetor (injector), engine, special sensors and other devices. But that shouldn't scare you. Knowing the root causes of a malfunction will help you identify the problem more quickly and possibly fix it yourself.

Main reasons

Let's highlight what causes the check engine lamp to light up, and how you can cope with the existing problem:

1. Low quality fuel. We have already talked about this a little above. If the malfunction was discovered almost immediately after refueling, then the best way is to drain the "dangerous" combustible mixture from the tank and fill in the normal one. If the lamp stops glowing, then you can continue driving. If not, then the malfunction will have to be looked for elsewhere.

2. Failed spark plugs. In practice, the "check engine" indicator can light up when the insulator on the spark plug is destroyed, the gap is broken, or there is a problem with the spark. In such a situation, the only way out is to unscrew the candles and inspect them. In case of obvious signs of damage, the presence of thick carbon deposits on the electrodes, a decrease (increase) in the permissible gap, it is advisable to replace the candle. By the way, the normal spark plug gap is about 1.3 mm.

3. Defective ignition coil. Make sure you have caviar on the spark plugs. If there are no problems here, then measure the resistance between the primary and secondary winding of the unit. In case of serious deviations from the norm, the coil should be replaced. The resistance parameters can be found in the technical documentation for the device (depending on the manufacturer and type, they may differ).

The primary resistance should be between 0.2 and 4 ohms. If the multimeter shows zero, then this indicates a short circuit inside the winding. In the case when the resistance is too high (or tends to infinity), then there is a high probability of an open circuit. The secondary resistance may vary. In some devices, this figure is 6-8 kOhm, while in others it is more than 15 kOhm.

A malfunction in the primary or secondary winding can lead to spark problems and, as a result, a "check engine" signal.

4. Lambda probe (air sensor) - another " headache»Car enthusiasts. Its malfunction very often causes the indicator we are discussing to light up. To discard (confirm) your suspicions, check the performance of this node. The oxygen sensor can fail for the following reasons:

• contact with brake (coolant) fluid on the casing of the device and its further penetration inside;

• the use of unsuitable compositions for cleaning the lambda probe;

• high content of lead in fuel (this happens very often at our gas stations);

• excessive heating of the case under the influence of neighboring mechanisms.

To check the device, proceed in the following sequence:

• read the instructions and pay special attention to the main indicators of the oxygen sensor (requirements for battery voltage, ignition timing, and so on);

• visually inspect the sensor for obvious contamination. If the surface of the device is completely covered with lead, soot or a strange coating, it is better to clean or replace it. If the lambda probe is visually clear, continue further investigation;

• disconnect the sensor from the power block and connect the multimeter probes to it. Start the car and turn on the gas up to 2500 rpm;

• set 200 rpm (this can be done using the fuel enrichment unit) and look at the readings of the device. If the dial is 0.9V, then the device is working normally. If the indicator is below 0.8 Volts, then we can talk about a sensor malfunction;

• simulate impoverishment fuel mixture... This is easy to do - take a vacuum hose and provoke additional air leaks. If the device is intact, then on the voltmeter you can see the indicator within 0.2 Volts;

• connect the sensor to the system, connect the multimeter probes in parallel and increase the speed to 1500. If the sensor is intact, the voltmeter will show about 0.5 volts.

5. Failure of the catalyst or its incorrect operation is another reason for the check engine lamp to come on. To rule out this version or confirm your suspicions, do a little check:

• dismantle the catalyst and visually inspect its honeycomb for light. If they are clogged, then it will be visible immediately. The only problem is that unscrewing the catalyst is a very difficult task;

• measure the level harmful substances in the exhaust. If there are noticeably more of them, then the catalyst is contaminated.

• check the back pressure in the exhaust system with a pressure gauge. The normal indicator with an open fuel valve is about 0.35 kg / cm3.

6. Clogged nozzles Is another common problem in modern cars. It is associated, as a rule, with poor fuel quality. The check can be done as follows:

• remove the injectors from the engine (some checks can be done directly on the engine);

• use a multimeter to measure the injector resistance. Please note that there are two types of atomizers - low (2-5 Ohm) and high (12-17 Ohm) impedance;

• listen to the work of the power unit. If a ringing and dull sound appears, then this is a clear sign of improper operation of the injectors;