Motor turnover sharply. Why engine speed is raised, then fall. Search for breakdown without using on-board controller

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The rotor drop is a sufficiently unpleasant incident for your car. It is not only about the inconvenience and the emergence of the issues of the serviceability of the car, but also about the work of important mechanisms. The problem is that a sharp drop of revolutions on idlingWhen the car rolls on a neutral gear, can drown out the engine, and this becomes dangerous for further movement. The driver may not notice such an incident, turn on the second gear and release the grip, which will cause a sharp braking by the engine. Auto can get "from the pusher" in this way, and it can just stop than creating an emergency. When driving a car, the drop of revolutions is also unpleasant to the driver's confidence. You have to constantly podge the foot or use other methods of engine retention in working condition. It is worth understanding the causes of the problem.

So, why do turns fall when warming on cars with a carburetor? You can find a lot of general reasons that combine owners as a specific auto model and a particular type of carburetors. It must be said that today the car with such a type of fuel injection is no longer released. This is not the most successful solution, since the carburetor is very sensitive to the quality and purity of fuel, it often requires maintenance and does not serve very well in different climatic conditions. For this type of gasoline injection, stability is necessary, but in our operating conditions provide such a luxury is simply impossible. Therefore, there are various problems that can lead to significant discomfort and even the danger of movement by car. Today we will look at the main reasons for a sharp or waveway drop of revolutions when warming on cars with carburetor fuel injection.

Perhaps the case is not in the technique, but in refueling?

As mentioned above, the carburetor is very sensitive to the quality of gasoline, which you pour into the tank of the car. If sacrifice or impurities come out, the technique will not work normally. Dirty gasoline to a certain pore is cleaned with a filter, but over time, such a cleaning ceases to help. Fuel with impurities and inclusions may be a big problem that affects not only the revolutions. Here are some important indicators of such a problem:

already a few kilometers after refueling by poor-quality gasoline, you will feel changes in the dynamics of the car, the fuel consumption will increase and stability will deteriorate;
engine turnover at idle can swim, and it will talk about the unstable fuel mixes, at speeds are also small jerks and failures in the aggregate traction;
after cooling the engine at the next start, the warming can start unexpectedly with low speedYou will have to play sawmill in unusual ranges;
it is also possible that after warming up to 30-40 degrees, a failure will arise, which will need to be compensated for by pulling out the supply until it stops or podging the foot;
when warming up operating temperature The motor will work relatively stable, but the speed of revolutions will remain, it is these indicators of poor-quality fuel in a car tank.

These criteria suggest that it is better not to go to the usual refueling for you. Of course, the same problems are possible if the carburetor fails and needs maintenance. But often these problems occur precisely with low-quality fuel low octane number or with impurities. Therefore, the first thing is to roll out the gasoline on a heated motor and add good tested fuel to it.

It is time to serve the carburetor - small defects

The reason for the fall of revolutions during warming can also be a small breakdown in the carburetor system. These are broken membranes, mixed fastening of cables or the showering of the damper. Such troubles can be cured during the audit of this device. In the old days, every second driver of the car could independently sort out the carburetor, install Remkomplekt and go further, listening to the satisfied rumbling of the unit. Today the principle of repair is as follows:

you should go to the automotive store or market to find a suitable repair kit for your type of carburetor, it is better to take original high-quality details;
it is further important to find a wizard who is well versed in carburetors and can help eliminate problems in your device, such masters in cities are less and less;
a specialist for several tens of minutes will move the equipment, will find a problem and establish new gaskets, membranes, seals and other products from the repair kit;
next, it is necessary to check the equipment to make sure that there is no unpleasant effects, it can often be done only the next day on the cooled car;
the last step is regular visits to the master 1 time in 2 years for maintenance and revision of the carburetor, this will allow you to save the car in a normal working condition.

There are advantages in the fuel injection carburetor injection. For maintenance and cleaning the injector will have to pay a whole condition. But the repair of the carburetor even with the replacement defined details It will not cost too expensive. But to get these advantages, find a master who is well familiar with the features of your car model. Such a specialist will help to correct all problems and continue to exploit the car without problems.

Condensate or dew point - is it possible?

On VAZ 2107 cars, the engine revolutions is very often occurring while warming up until the aggregate stops. Such trouble is characteristic of all carburetors, except for Saleks. The problem is that at temperatures from 0 to +5 degrees in the chambers of the carburetor, condensate can be collected. This is a specific type of dew, which is formed during temperature drops. After starting the motor to the cold, the following process occurs:

first, the open sublicas launches the enriched mixture, which without problems burns and does not cause tangible changes in the work. power aggregatethat is very important for normal launch;
as the owner of the car lowers the sublicas, the mixture is approaching the characteristics to the worker, and the entire engine system is already a little fundamental, and the most interesting thing begins here;
condensate or dew start to enter this mixture and change its properties, in some models of devices it happens quite quickly and unpleasantly, causing a stop of the motor;
the driver again pulls out the seats or presses the gas pedal, the mixture is enriched, the motor is working normally, but up to 60-70 degrees this process may be repeated infinitely;
after warming up to about the operating temperature, everything is normalized, the revolutions come back to normal, the engine works well, so when a visit to the station, the wizard will not detect anything.

How to deal with such a situation, it is difficult to even imagine. The only one in an effective way There will be a replacement of the carburetor to the Solex, but also in these models there are often problems with the launch of the power unit in transition temperatures. So give any specific advice in this case is not easy. Best to maintain equipment in time and always support fuel equipment In good condition, it will help to get due reliability of the machine.

Are there any other reasons for a sharp drop of revolutions?

The causes of such trouble can be a whole set. If you repair the car yourself, it is worth a slightly look at trouble and try to find reasons in other nodes. But it is worth moving to other features of the car only if you were convinced of the high quality of the carburetor, normal fuel and other features mentioned above. Here are some more ideas for checking:

fuel filters - very often filter elements are clogged, and the owners forget to change them in time, and this leads to serious problems with the vehicle;
the thermostat is possible after a minor habit of a small circle, your thermostat opens and keeps sharply ice fluid into the engine, which leads to a drop of revolutions;
electronics - It is worth checking the ignition, a normal timing belt setting, no problems with sensors and various electronic equipment on board your car;
the inclusion of electricity consumers - perhaps, in your car automatically turns onto a powerful device, which gives the load on the unit, the revolutions are inevitably falling;
the valve system - sharp drops and drops in this case will not be, but floating and unstable turnover are quite possible, and with the load they will turn into a fall.

The reasons for the instability of the engine operation can be a lot. Sometimes the problem is that the generator at a certain point ceases to give normal voltage, which affects work electrical systems Engine. The load on the motor can also be due to poor oil or internal breakdowns in the cylinder block or in the valve system. So you can dig in this case for quite a long time, and it is better to visit a hundred and find the cause of the problem.

We offer to watch a video with a solution to one of possible causes This problem:

Let's sum up

There are dozens of breakdowns that lead to a sharp or smooth drop of revolutions on carburetor cars. But the question is that the equipment turns out to be quite demanding for service, therefore, it is necessary to eliminate all the reasons to be taken together. If you always encounter such a problem, it means that this is the specifics of the carburetor, installed in your car. Most likely, only replacing the device will help get rid of trouble. If the trouble arose only a few times, it is worth trying to serve the fuel system, replace the filter and install a new carburetor repair kit.

Auto with such a type of injection is gradually inferior to injection systems. They are more reliable, more economical, serve longer and do not bring such trouble as carburetors. Of course, in the immediate injection there are also many subtleties and features that should be remembered. But changing the carburetor on the injector is too labor-intensive and expensive. It is better to maintain your technique and achieve its normal work. Even with very good services, after 1-2 years, you will have to go to the service again. Have you ever encountered a sharp drop of engine speed when warming up?

Compared to the past carburetor generation, the new injector VAZ 2114 turned out to be much more efficient and more reliable, but from time to time and they are pursued by various problems. This situation, as a drop in revolutions, after resetting gas to the VAZ 2114 is almost always caused by problems in the operation of the injection system, but other reasons should be eliminated during the diagnostic process.

How to find the cause of the problem

If the VAZ 2114 turns are falling, it is necessary to comprehensively digitize the functioning of the injection system on its car, which can be done in itself in the garage in the presence of small experience and relevant instructions. An important advantage in this case is those "fourteenth", which from the factory came across dashboard From the German VDO manufacturer, as it is, compared with the analogue from the score, is equipped with a self-diagnosis regime.

To carry out this procedure, you will need to perform several non-speed actions:

loading the motor, you need three or five seconds to keep the odometer button down;
transfering the ignition of the engine to the first position, the button must be released;
the arrow should appear on the display, which is a signal about normal operation, then the button must be pressing the first (display of the firmware version) and the second time - after that there will be probable errors in the ECU;
to reset the error message, you will need to hold the button before the zero appears on the display.

Having read the manual, you can find out which errors shown on the screen can be related to the fact that turns are constantly falling when the gas is discharged to the VAZ 2114.

So, it may be one of the following situations:

code 1 - controller error;
code 14/15 - Cooling fluid sensor error;
code 22/23 - position sensor error throttle valve;
code 33/34 - sensor error mass flow air;
code 42 - faulty ignition;
code 44 - depleted or too rich fuel mixture.

The owner of the VAZ 2114 should be remembered on the specific features of the work of self-diagnosis on its auto: if there are several errors, the computer summarizes their codes arithmetic, which can be misleading. Specify this can a logical inconsistency of the displayed code of actually available problems.

For full confidence It will be necessary either to take the car to the service and pay for its inspection, or to buy a diagnostic scanner itself, which is not so expensive. Another option - in the presence of the same model of the VAZ (fully serviceable), take turns from it and put on your car potentially vulnerable sensors, the exclusion method I find out the problem.

Search for breakdown without using on-board controller

The external "symptoms" of the behavior of the car and, in particular, its engine can also give a lot of food to think about the experienced and observation driver. Analyzing these factors, you can significantly reduce the list of probable causes of malfunction.

For example, you need to track the moment of arbitrary engine drill - at idle, with a cold start, after heating the engine to a specific temperature or when harsh pressed on the gas pedal.

In addition, you should pay attention, whether turnover is falling at a constant podgezka, and how does the engine behave when braking, release the gas pedal and turn off the transmission?

In terms of visual-audible diagnostics, it will be worthwhile to check the circle potentially vulnerable nodes that can lead to the fact that the VAZ 2114 stalls when the gas is discharged.

First, you should start with the check of fuel and air filters - change them is recommended every 30 thousand kilometers, but in fact, the operating conditions and the quality of filters leads to the fact that to avoid problems, it is better to reduce this period halve (especially since machines with cars big mileage Filters clog even faster).

In addition, it is necessary to check the fuel level in the tank, no matter how ridiculous it sounds: the fuel level sensor often deceives the driver, and in addition, the car can tritely stand on a slope, because of which the fuel pump simply does not supply fuel to the engine - hence and The reason for the turning distance.

Very common situation - the appearance of problems with ignition or retention of revolutions after small independent repair: In this case, you need to check all the chips, contacts, terminals and wiring to exclude the usual human factor again.

Rolls on neutral transmission

If the VAZ 2114 is falling and stalls the engine "on the cold", probable causes of problems are not so much: the failure of the fuel pump, breaking the idle regulator, which is lit injector or failure in the cooling fluid temperature sensor.

The main ways to solve situations are the following:

1. If the reason in the idle regulator, the engine will constantly trim in this mode, and not just stupid. For the diagnosis of PXX, the multimeter, which, with a muffled engine, measure the resistance: on terminals A - B, C - D, it should be equal to approximately 54 ohms, whereas there will be equal to infinity between pairs. Any deviation from these indicators should be considered a malfunction.

1. The dirty injector is a very common situation, if you consider how poor quality gasoline trades on most refills: can sometimes help special tools To clean the injector. Worse, when the nozzles clogged - if the cleaning agents did not help, you will have to change them or carry it into the service for cleaning.
2. The failure of the gas station is usually preceded by characteristic signs of violations in its operation: the attentive driver long before the breakdown will hear the difference in the sound of the pump when the engine is started. If there is no problem with a slocessing engine when driving on transmission, but idle occurs, you can pre-check the fine filter.

Sometimes candles can be out of order, which direct affects the work of the entire ignition system, but regularly replacing them in preventive purposes pre-warns the emergence of the problem. Additionally, it is recommended to check the state of the ignition coil.

Malfunction in the operation of the sensors

The normal functioning of the injection motor on the VAZ 2114 is ensured by the correct operation of the four key sensors: the position of the throttle, mass flow of air, the position of the crankshaft and the temperature of the coolant.

Throttle Position Sensor VAZ 2114

It is necessary that all power unitsystem systems work properly. In this case, the engine must work normally both under load and in idle mode.

In practice, often the drivers face a problem when the engine turnover is not falling or falling with a large delay after discharge gas. It is obvious that overestimated idling Indicate problems and are the cause of increased fuel consumption.

In this article we will talk about why motor turns do not fall, as well as consider the main reasons why similar problems arise on and auto.

Read in this article

When resetting the gas, turns are increased or "hang": common malfunctions

Let's start with the fact that on many cars with an injector during heating the turns raises. This is necessary in order for the power unit to work steadily after a cold start.

However, after increasing the temperature, the control unit lowers the turnover of XX, bringing them to normal. On many cars with a carburetor, the driver independently increases the revolutions during heating, using the so-called "SUPPLC".

At the same time, after the engine is heated, the idle speed is normal, on average, 650-950 rpm. If you click on the gas and release the accelerator, the turns should be increased, after which it is again dropped to the specified values.

It also often occurs when the momentum is slowly reset or constantly held at a mark of 1.5 thousand rpm, 2 thousand revolutions, etc. Expensely, in such cases, the flow rate is increasing and is stronger than the DVS, which indicates the need for diagnostics.

So, let's start with frequent problems Carburetor. Often the engine speed is not discharged due to the problem with the throttle. For example, when the driver presses the gas, the damper must be opened wider so that more air to burn the fuel in the cylinders. After the gas pedal is released, the damper is closed, revolutions are reduced.

If the damper does not close to the end, the re-entered mixture is incorporated into the cylinders, revolutions are increased. The reason may be strong pollution of the throttle node or damage to the damper itself (deformation). To begin with, clean the flap, the liquid for cleaning the carburetor is suitable as a cleaner.

We also note that the damper is closed and in the case when the drive cable is worn. In this case, the cable is subject to replacement. On carburetor machines do not fall engine speeds often and in the event that the gasket between the carburetor and failed. Also, the culprit may be an intake manifold, which has damage.

The main task becomes the right ratio of the amount of fuel and air. Often high level Fuel in a float chamber of the carburetor also leads to increased revs. Check should be started with a needle valve.

We now turn to the injector. Pay attention to many injection cars. As for malfunctions, the injection system itself is more difficult, that is, the causes of high revolutions are more compared to the carburetor.

As a rule, circulation problems can be caused by malfunctions of both mechanical elements and electronic components. In the list of major malfunctions, experts identify disorders of the temperature sensor, which is installed in.

Simple wordsIf the specified sensor supplies an incorrect signal, the ECU believes that the engine is cold and the warm-up mode. In this case, the control unit raises the momentum so that the power unit worked stably and faster to operate.

Also, revolutions problems may begin due to problems and failures in the work (idle regulator). It also happens that the throttle cable is hired and twisted. Another spring that closes the throttle can stretch or cause damaged.

Separate attention should be paid to the gaskets, since the air drums can lead to the fact that the mixing formation is disturbed. This means that you need to separately inspect the laying of collectors, nozzles seals, etc.

Floating turnover: Causes

Note that in some cases, the turnover is not just slowly falling or kept at one level, but "float". In this case, the engine can work unstable. First fall, then grow sharply and everything is repeated. Frequent cause of such a phenomenon is the supply of excess air, which leads to the "jumps" of turns on the XX.

Such problems arise in case of failure of the air supply sensor (), which allows the ECU to calculate how much air has been received and how much fuel is applied to prepare the necessary mixture.

If the failures arise, the control unit cannot prepare the "correct" mixture for the XX mode, which causes speed jumps after the release of the gas pedal or during the operation of the motor at idle.

Let's summarize

As you can see, to accurately determine why the engine turns are not reset, in many cases there may be in-depth diagnosis. For carburetor engines, cleaning and adjustment of the carburetor itself is often needed, while for the injector it will be necessary.

If the problem does not lie on the surface (zakis the valve cable, after washing or dry cleaning, the mat is incorrectly laid in the cabin, which presses the gas pedal, etc.), then it is better to deliver the car to the service.

The most difficult situation is such when it assumes the presence of a large number of sensors and actuators. In this case, even use diagnostic equipment It does not always allow you to quickly and accurately determine the problem.

If the diagnosis is difficult to optimally deliver the car to such a service that specializes in the repair of a particular car brand. As a rule, these are official dealerships, less often you can meet third-party organizations.

Finally, we note that the timely detection of the problem allows you to save other nodes and aggregates. In other words, high curvatures of XX, speeding turns and jumps indicate that there are problems with air / fuel supply or with mixing formation. Ignoring such problems negatively affects the engine and the service life.

Common Causes of idle instability

Injector and carburetor engines have a practically the same ignition system. The most common cause of failures is associated with damage to the candle wires. Their device is such that it is not always possible to check the service life. Moreover, the removal and fixed wire can show the correct values \u200b\u200bof resistance, and when vibrations work is unstable. The insulation test can sometimes be noted in the dark on a blurred glow in damaged places. The best way Checks - Installing knowingly serviceable ignition wires. If the engine work has changed for the better, it means high voltage wires Require a replacement. When the engine revolutions fall into crude weather, the candle wires are also most likely to blame.

IN carburetor engines The culprit can serve.

Turns fell during sucking air

Why do turns fall in this case? Sometimes the engine speed jumps during air sucks after a carburetor or a mass flow sensor. IN carburetor system Power This causes depletion of the working mixture, and in the injection in the testimony of the air flow sensor in the cylinder, one quantity comes, and actually a little more, which also imposes a working mixture.

To check, you need to use the aerosol for flushing carburetors. It needs to be sprayed in suspicious places of connections during the operation of the motor. Changing the nature of the work (usually turns sharply increase) will indicate the air suction site.

In motors equipped with an oxygen sensor (lambda probe), the source of problems may be air seepage in the graduation path on the site to the lambda probe. It, determining the excess air after the combustion chamber, believes that the mixture is depleted, and increases the supply of fuel, resulting in, accordingly, the rotation of the engine motor is float.

Faults of the idling system of carburetor engines

In the old aggregates with the carburetor, the most frequent cause of failures lies in clogging of idling jets in fiberglass in fuel or resin deposits, also falling together with fuel. In the carburetors with the electromagnetic valve of idling, it is the valve that can cause incorrect operation of the system.

To check, you need to remove the power connector from the valve on the stopped motor and then put it on the place. The absence of a characteristic click will prompt about the malfunction of the electromagnetic valve.

To wash the carburetor at home, you can use fluid for washing in an aerosol can be used.

Malfunctions of the idling system of injection engines

IN injector cars The culprit that idle speed jump is most often the idle regulator. It is a rod whose height is regulated stepper electric motor. Pollution of rod resin sediments from poor-quality fuel is most common. The stock at the same time moves sharply, jerks, in certain areas it can be fully stalled, at the same time single engine turns are floating. Mixed sediments with liquid for flushing carburetors.

Strictly speaking, almost all sensors can affect idle instability. Starting from the mass flow sensor and ending with a lambda probe. The search for a faulty item is more convenient to produce with the diagnostic system. If the car is equipped with an on-board controller, then it will be an error code adopted in this device. By code, you can determine which of the data items is faulty.

Checking for distribution and crankshaft position sensors

Some sensors can be checked. This is a mass flow sensor, distribution Vala. And the crankshaft sensor. The last two are diagnosed by connecting the voltmeter to the mass and the signal wire when the ignition is turned on, but the unused engine. With slow rotation crankshaft The device will show periodic voltage jumps. If the crankshaft sensor malfunction, the motor is most likely not started, but with a non-working camshaft sensor (phase sensor) engine will work. Only at the same time, and when moving, failures or an arbitrary increase in revolutions are possible, since the power system proceeds from the phased injection mode to the simultaneous injection mode, and the revolutions will jump regardless of the motion mode.

Checking the fuel consumption sensor

To check this item, a digital voltmeter is needed with a measurement limit of 2 V. Voltmeter connects to the DMRV signal terminals when the ignition is turned on. In particular, on a vase, it is terminals 1 and 3. The voltage value of a good element should be in the range of 0.99-1.01 V. Voltage more than 1.05 V speaks of its failure. In this case, interruptions in the engine work in all modes are possible.

The sensor under consideration is not subject to repair. Moisture hit on it when washing the sensitive element, it is guaranteed to displaced it.

Floating turnover with a faulty oxygen sensor

The oxygen sensor, or the lambda probe, measures the oxygen content in the exhaust gases and based on the obtained data determines the quality parameters of the working mixture, issuing a signal for depletion or enriching it. The device works normally only after it warms up to operating temperature - at least 300 degrees. Therefore, most of them are complemented by an indirect heating system to accelerate the output to operating mode. The fault of heating or contamination of the working surfaces of the sensors of combustion products causes inaccuracies in determining the oxygen content, as a result of which the engine operation will be unstable.

temperature sensor

The electronic control unit (ECU) when starting a cold engine increases idling speed, since at low temperatures, the engine is unstable, and it can stumble. As the temperature increases, the ECU gradually reduces the revolutions and leads to a minimum when the minimum operating temperature is reached. To measure it, the coolant temperature sensor installed on the cylinder block is used. It should not be confused with a temperature sensor installed on the radiator, which serves to turn on the fan.

Checking the temperature sensor is carried out by measuring its resistance to the ohmmeter. A good element at room temperature has a resistance of several tens of decisions, and when heated to 200 degrees (you can take advantage of a lighter) drops ten times. If the instrument readings sensor are not changed when the sensor is heated, then it can be concluded that it is faulty.

Conclusion

We looked at several situations in which engine speed float. To solve the problem, accurately setting its reason, it is better to refer to the specialists to the station.

Motor - "Heart" of the car, and like the heart of a person, in the work of this "organ" sometimes interruptions occur. We are becoming known about the rhythm of his "heartbeats" to the rhythm of its "heartbeat". If the momentum of the power unit began to swim - the motor gives us a signal that something is wrong with it. In our today's material, we will tell, on what breakdowns are hinting for the rings of the engine, how to properly diagnose and repairing them.

The reason for the appearance of floating turns

The fact that the motor has something wrong with turns, the driver can learn by looking at the tachometer. During the normal operation of the power unit at idle, the arrow of this device is kept at one level (usually within 750-800 rpm), and if the engine has a problem, then the arrow drops, it rises (range from 500 to 1,500 rpm and higher). If there is no tachometer in the car, then floating turns can be caught on the rumor: the engine rockness increases, it decreases. And also - on the growing and weakening, penetrating the car from the engine compartment.

As a rule, unstable engine speeds manifest on idle. But even on the intermediate turnover of the motor operation, you can fix the failures or the tachometer arrow, this is characteristic of. Consider these two cases separately to understand what reasons these phenomena occur.

Experience races at idle

Floating speed at idle are most often manifested by injector engines. This is due to the peculiarity of the operation of the idle system. electronic block Engine control (ECU). The electronic "brains" of the car constantly read information about the operation of idling, and if it is broken, they give the command responsible for the correct operation of the system to correct the sensors. The work of idling may be violated due to improper air to the fuel system, and specifically - in the engine cylinders. In this case, the mass flow sensor of air signals the ECU on the combustion chamber of the air. To align the amount of air and fuel forming the fuel-air mixture, brains give the command to the injector valves to open and let the cylinders more fuel. At this point, the engine turns sharply increase. Then the ECU "understands" that he filed too much fuel to the cylinder, and restricts his feed - at this moment the turns fall sharply.

The second reason for swimming speeds at idle is the failure of the idle regulator ().

It is an electric motor, in the design of which a conical needle includes a cone, and the function of it is to stabilize the rotation of the motor when it works faster. The main cause of its breakdown is the wear of the elements of the RCX (wire break, wear the guide or the drive of the conical needle and other) due to the long-term operation of the vehicle on poor-quality fuel. When the regulator breaks, the engine, remaining without a "stabilizer", begins to involuntinate or lower the revolutions.

The third reason for revolutions - Ventilation valve malfunction oil Carter.

In the process of operation of the motor in the crankcase, spent gases accumulate (they are also called crankcase). If the engine is new, then the volume of such gases in the crankcase is relatively small, and the motor with a large mileage the amount of crankcase gases is increased. The excess of these gases is displayed through the ventilation system to the intake manifold and the throttle, where they are involved in the formation of the fuel and air mixture in the engine combustion chambers. If the crankcase ventilation valve encins (usually it happens because of the deposits on its walls of oil residues contained in the crankcase gases), there is a smaller amount of crankcase gases in the intake manifold, the TVZ is not fully enriched, the engine turnover begin to float - from medium ( 1100 - 1200) Low (750-800).

The fourth reason for the appearance of floating revolutions at idle is the failure of the air flow sensor ().

It, as well as the crankcase ventilation valve, can be covered with a dirty oil film in the process of long-term operation, which, in the end, leads to its breakdown. A thermomemometer is quite rare in DMRV - an element responsible for measuring air volumes entering the engine combustion chamber. ECU in this case does not receive correct data on the mass consumption of air and requires it to feed it in the cylinders, which responds at the rollers of the motor.

The fifth reason is the incorrect operation of the throttle, the function of which consists in adjusting the air pressure supplied to the motor cylinders.

It can be jammed for two reasons: an oil field appears on the inner surface of the "Pigalok" of the flap, which does not allow the flap to close and open, and also due to the malfunction of the throttle drive. It should be noted that this is the most common cause of the operation of a motor with floating turnover at idle, characteristic and for carburetor engines.

Speaking about carburetor engines, we will list the reasons why they can have racs at idle. This is a) incorrect adjustment of the idling motor; b) breakage of the electromagnetic valve of the carburetor; c) clogging of idling gibber products of fuel combustion.

Rapchildren at intermediate go

W. diesel engines Floating turnover at intermediate moves mainly occur due to the formation of rust on the blades in the fuel pump high pressure. Corrosion of these parts of the pump occurs due to the presence of water fuel. By the way, for the same reason turns diesel engine jump and idle.

All the above causes of the appearance of unstable engine speeds have several consequences: fuel, emissions to the atmosphere exhaust gases With a high content of CO, the wear of the fuel system elements and the engine air supply system. To prevent this, it is necessary to periodically check the work of the systems listed above and sensors, and if the trouble happened, and the turnover "fever" is to immediately repair all the breakdowns.

Correct the floating rotation of the motor

1. Air Soothing in Engine Cylinders. It is necessary to check the tightness of the highways of the air supply system to the intake manifold. To do this, you can shoot each hose separately and blow it with a compressor or pump (time-consuming process), and you can process WD-40 hoses. At the place where "Wader" will quickly evaporate, it will be possible to detect a crack. In this case, we recommend not to stick it with a tape, but replace the worn hose to the new one.

2. Replacing the idle regulator. The state of the RXX is checked with a multimeter that measure its resistance. If the multimeter shows the resistance in the range from 40 to 80 ohms, then the regulator failed and it will have to be replaced.

3. Cleanter Ventilation Valve Cleaning. It is not necessary to do without disassembling the oil crankcase - only this can be reached to its ventilation and remove the valve. We rinse it in kerosene or any means to clean the engine parts from traces of oil sludge. Then we dry the valve and install it in place.

4. Replacing the air flow sensor. DMRV - Detail Delicate and in most cases repair is not subject to repair. So, if he was the cause of floating revolutions at idle, it is better to replace it, and not repair. Moreover, it is impossible to correct the failed thermoemometer.

5. Flushing throttle with subsequent installation of it proper position . There are two ways from oil sediments - with removing the damper and flushing it without removing from the car. In the first case, we disconnect all the hoses and wires leading to the flap, weaken its attachments and take out. Then put in the container and pour a special aerosol (for example, Liqui Moly. PRO-LINE DROSSELKLAPPEN-REINIGER).

If the oil sludge on its surface is forced, it can be carefully cleaned with a brush. Then the flap surfaces to get into a clean dry wind and install it in place, connecting all hoses and wires. In the second case, flushing the throttle valve is carried out on the hot engine with the same aerosol. Before applying a cleaning agent, the damper must be de-energized. First, pour an aerosol inside the damper, we wait a couple of minutes and start the engine. When the motor is running, continue processing an aerosol damper. If the white smoke sweat from it is not scary, it is removed oil sludge. At the end of the procedure, connect the wires, and with the help of a computer, we reprogram the algorithm for its operation by installing the desired gap opening clearance.

6 .. This operation can be carried out using a screwdriver, adjusting the screws of the number and quality of revolutions.

7. Replacing the solenoid valve of the carburetor. When breaking this valve, the engine can only work on the air seats. Therefore, to eliminate speed jumps, we recommend replacing the electromagnetic valve to the new one.

8. Cleaning of idling bicker. Twenty years ago, the purification of gibera from oil plated was a time-consuming operation. Today it is not necessary to extract the fatter from the system - it is enough to pour into it a special aerosol for cleaning carburetors and leave the remedy there for five minutes. After this time, it is necessary to clean the loaf from the residues of dirt with compressed air.

9. Treatment of blades of TNVD from corrosion. To do this, it will take a means of corrosion (for example, Xado Verylube.) that can be simply sprayed in the neck fuel tank Before refueling. Cleaning the blades of the pump from corrosion This means will perform independently. To prevent corrosion of the pump blades, you can pour into the tank 200 ml motor oilWhich in the process of driving will create a protective film on the surfaces of the blades.

Remember: when the engine revolutions appears at idle speed, it is necessary to contact the service station and conduct a detailed check of the operation of the indicated engine systems. Timely diagnostics will save you from serious breakdown of motor assemblies.