The car pulls poorly and jerks. Lost engine thrust: why does this happen and what should the driver do?

22.04.2020

A hefty book could be written on this topic. However, a lot of these have been written today: anyone who is interested will definitely find it and read it carefully. We will try to identify the main reasons for this disorder.

First, let's remember what the engine needs to work. It is necessary to create the correct fuel-air mixture, which should be set on fire in time. Therefore, if it is of poor quality or is not supplied in the proper quantity, then you cannot expect good traction from the engine. At low octane, the engine management system will advance the ignition timing to the latest (and is still possible). If the performance of the fuel pump is insufficient or the filter is clogged, there will simply not be enough fuel. The quality of fuel atomization by injectors also affects mixture formation. If they are coked and do not form the correct fuel flame, then the proper composition of the mixture cannot be expected either.

For the correct formation of the mixture, another component is needed -. And if the air filter is excessively clogged, the engine management system will see a lack of air and limit the fuel supply, which will certainly reduce power. At the same time, the intake of air not taken into account by the engine control system will also disrupt all calculations.

Now about the combustion initiators - spark plugs and coils that provide them with high voltage pulses. If these components in at least one of the cylinders are not working properly, then they are not getting enough power.
Optimal filling of the cylinders with the working mixture and timely removal of exhaust gases depends on the correct valve timing. Therefore, jumping the timing belt or chain even by one tooth will undoubtedly lead to a drop in power.

To ensure an optimal combustion process, the mixture must be compressed. Therefore, cylinder wear, which reduces , has the most negative effect on engine thrust.
An insufficiently warmed-up engine produces less power, not only because viscous oil resists movement more strongly, but also because the injection system itself limits the parameters. And the engine can be underheated either temporarily, during periods of severe cold, or permanently - for example, with a faulty thermostat.
The burnt mixture must be removed in a timely manner, so the influence of the exhaust system on engine power is also significant. If the resistance to gases escaping is high, don’t expect any parameters from the engine. Resistance can increase either due to clogged or jammed exhaust system pipes.

What else? Besides the engine, the car has other reasons for losing its initial agility. For example, a slipping clutch is worn out or incorrectly adjusted: you press on the pedal, the engine responds, but the car barely crawls... you can also joke: the most commonplace option is the parking brake sticking.

If we have missed any reasons, please supplement the material with your own thoughts.

Sometimes owners of products from the domestic automobile industry are faced with a situation where they cannot injection engine on a VAZ 2114. This problem is not uncommon, so let’s try to carefully understand the reasons for the “weakness” of the engine and eliminate them ourselves.

List of possible causes of power loss

Not every driver, even an experienced one, can quickly answer the question: why the thrust of the VAZ 2114 engine with 8 valves disappeared the first time.

To do this, you need to consider all possible sources of failure:

debris entering the gasoline filter;
clogged fuel pump diaphragm;
malfunction of the sensor that controls air flow;
poor spark plug performance;
ECU malfunction ( electronic unit engine control);
dusty air filter;
clogged injectors;
complete wear of the clutch disc;
insufficient compression in the cylinders.

Analysis of the causes of poor engine traction and possible repairs

Fuel filter dirty

This may be due to low-quality gasoline (containing various small debris) or infrequent cleaning fuel tank. In this case, you will have to completely replace the entire filter system.

Fuel pump diaphragm clogged

The cause of the blockage, as a rule, is low-quality gasoline. To clean it, just remove the diaphragm and rinse it thoroughly or blow it with air.

Malfunction of the sensor that controls air flow

This is the most common reason why the VAZ 2114 does not work.

Signs of malfunction:

too high or low revs engine idling;
intermittent engine idling;
disturbed acceleration dynamics. The car becomes uncontrollable and often freezes.

It is worth periodically checking the operating condition of the air flow meter to avoid wasting time and money diagnosing the engine.

Air filter dust

The more the filter is clogged with dust, the less air flows to the engine, therefore, the thrust decreases. What can be done in this case? Ideally, the filter should be replaced with a new one, but if this is not possible, you should remove the filter, tap and blow to remove large debris (flies, dry leaves, insects).

Clogged injectors

If the injector nozzles are clogged, you will have to go to a service station for ultrasonic cleaning, or purchase special liquid for the cleaning.

Auto mechanics advise purchasing only high-quality injector cleaning products, for example, Wynn’s (Vince), LIQUI MOLY, Carbon Clean.

The procedure itself is quite simple: the cleaning agent needs to be poured into the gas tank. But this method can only help if fuel system not very dirty. An engine with several hundred thousand kilometers will most likely need complete replacement injectors.

Complete wear of the clutch disc

You can determine disk wear by the following signs:

the pedal is easily “recessed”, but does not return;
the clutch slips;
when the clutch is engaged, a noticeable vibration occurs;
it is impossible to disengage the clutch.

There is another way to check wear: if you try to move off in fourth gear and the engine stalls, then there are no problems with the disc. If the engine continues to run, then the clutch disc will probably have to be replaced.

Poor spark plug performance

There are several signs by which you can identify a faulty spark plug:

at idle the engine makes an unpleasant noise;
a sharp press on the gas causes power failures;
the engine runs unevenly;
increased fuel consumption with reduced power;
the spark plugs are filled with gasoline.

Visual inspection of the spark plugs can also help identify the problem. If the candle is covered with dark oil, has a gloss or velvety soot, then this clearly indicates problems.

Defective spark plugs must be replaced with new ones.

Insufficient compression in cylinders

This defect appears due to high wear of the entire cylinder-piston system. As a result, the car owner notices that oil consumption increases, the combustible mixture does not burn completely, and fuel enters the crankcase. This problem is serious and can be solved either by replacing piston rings, or complete renovation engine at a service station.

Malfunction of the electronic engine control unit (ECU)

There may be several signs of an ECU malfunction:

various mechanical damages on it;
lack of indicators from various sensors monitoring systems;
lack of control signals for the fuel pump, system idle move machines and other mechanisms controlled by the computer.

Unfortunately, this device cannot be repaired in most cases. Even service station specialists will offer to simply replace the ECU with a new one after carrying out diagnostics.

Finally

The article lists all the possible reasons why the VAZ 2114 does not pull. Analyze them yourself and figure out the reason poor traction engine is within the power of every car enthusiast. This will save a significant amount of money compared to the cost of diagnostics at a service center.

As a rule, during long-term operation vehicle Almost every driver sooner or later notices that the engine does not pull well. In other words, power unit has difficulty coping with loads, loss is noted, the unit needs to be spun up to high speed to maintain the usual pace, the car accelerates worse from a standstill, picks up speed slowly, etc.

At the same time, in many cases the motor runs smoothly, without shaking, knocking or noise during operation. Let us note right away that there is a fairly wide list possible reasons where the heated engine does not pull, there is a loss of engine power when cold and/or when hot.

In this article we will talk about why the engine does not pull, and also consider the most common malfunctions that manifest themselves in the form of loss of traction of the power unit.

Read in this article

The engine does not pull: the main reasons for the decrease in engine power

So, if no other symptoms other than loss of traction are detected, then you immediately need to pay attention to the quality of the fuel, the proper functioning of the system, etc.

As practice shows, more than half of the cases of reduced efficiency from internal combustion engines are associated with fuel. The engine does not pull due to the fact that the tank may be filled with poor quality or unsuitable of this type engine fuel (for example, 92nd gasoline instead of 95th).

In some cases, after refueling, problems may also arise with starting the engine, and the engine appears. To solve this problem, it is often enough to dilute the existing fuel with a higher quality one. Less often, it becomes necessary to completely drain the fuel from the tank, after which additional flushing of the power system is performed.

Typically, such manipulations are necessary when, parallel to the loss of traction, unstable operation of the internal combustion engine is noted, and under load, the engine is difficult to start, on the panel, etc.

Also the owners gasoline engines can independently determine the quality of gasoline. To check the spark plugs you need to unscrew them from the engine. A disruption in the combustion process of the fuel-air mixture in the cylinders, as well as the presence of impurities in the fuel, can be identified by soot on the spark plugs and its color.

For example, if the fuel contains a lot of third-party metal-containing additives and additives, then the skirt and electrodes may become covered with reddish soot (brick-colored). Black soot will indicate that the fuel is not burning properly, etc. In any case, malfunctions in the combustion process of the working mixture lead to the fact that the engine stops pulling.

The next step in diagnosis is. A decrease in the efficiency of these elements is also accompanied by a decrease in the power of the power unit.

This is especially noticeable during sharp accelerations, and when the car is already moving at high speed. In other words, the motor has no “reserve” left for further acceleration.

The candles may be dirty, and it is also possible that their life has come to an end. To eliminate this problem, you can produce or immediately replace the entire set with a new one.

It is important to consider that if new spark plugs are correctly selected for specific engine according to the heat rating and other parameters, but they still quickly become dirty, then the reason for the loss of traction is not in them. The formation of carbon deposits in this case indicates problems with mixture formation or combustion of the fuel charge in the cylinders.

If everything is in order with the spark plugs, then you need to check the condition of the fuel and air filters. In the first case, insufficient throughput can lead to the fact that the cylinders are not supplied required quantity fuel for preparing the so-called “power” mixture.

As a result, the engine loses power, that is, it does not pull under load. In such a situation, it is enough to replace the specified filter element. As for the air filter, the problem is similar to the fuel filter, but in this case there is a lack of air in the fuel-air mixture.

This leads to the fact that fuel without a sufficient amount of oxygen burns incompletely. In such conditions, engine power naturally drops, carbon deposits form in the combustion chamber, spark plugs become increasingly dirty, etc. To solve the problem it also needs to be replaced.

Malfunctions of the power supply system, ignition and impaired mixture formation

If problems with spark plugs and filters can be identified right on the road, then more serious problems problems associated with the power and ignition system are much more difficult to diagnose and eliminate on site. In cases where the engine does not pick up speed, and jerks and dips are noted when pressing the gas pedal, it is necessary to check the injector.

Let's focus on the more common electronic injection. The list of main malfunctions of modern injection internal combustion engines highlight:

malfunctions, decreased performance or contamination of the fuel pump mesh filter;
malfunction of injection nozzles;
problems with sensors or ECU;
ignition system malfunctions;
air leaks and leaking fuel lines;

If we talk about the ignition system, in addition to the spark plugs, you should also check the ignition coils, etc. As for the fuel supply, at the initial stage you should measure the pressure in the fuel rail (rail). At the same time, the pressure regulator in the fuel rail is also checked.

Often, problems with many cars are related to fuel pump, which is located in the gas tank, as well as with the specified regulator. To measure fuel pressure, a pressure gauge is connected to the rail; the obtained values are compared with those recommended for a particular engine. If the pressure is below normal, then the culprit may be either the fuel pump or the pressure regulator.

The regulator's task is to discharge excess fuel into the return line at a time when the pressure is higher than normal. If the settings are incorrect or the regulator itself is leaking or faulty, then the fuel will be discharged into the return line ahead of time. To check this, air is pumped in with a compressor or pump, and the pressure in the rail increases. If the regulator operates earlier than the recommended pressure, the element must be adjusted or replaced.

Other reasons for reduced engine performance

The condition of the motor also greatly influences the power of the motor. The point is that for protection environment from harmful emissions During operation of the internal combustion engine, catalytic converters are installed in the exhaust.

During operation, the filter catalyst may be destroyed, reducing the throughput of the exhaust system. As a result, the engine is “strangled”. The check is carried out by measuring the pressure before and after the catalyst. You can also remove the element and inspect its condition visually.

As a rule, official services offer to replace a worn-out element, but the price of the spare part is very high. For this reason, on many cars in the CIS, the catalyst is simply knocked out, and the control unit is “deceived” by software or other available methods.

Also, when engine power decreases, it is necessary to check separately to eliminate the possibility of valve timing failure. Sometimes there are situations when the belt can jump one tooth, the chain stretches, etc.

In this case, the synchronous operation of the valve mechanism in relation to the operating cycles of the internal combustion engine may be disrupted. This leads to various failures, unstable work unit and reduced power.

Let us also add that engine wear and certain malfunctions also affect engine power. As a rule, worn-out internal combustion engines with mileage usually lose about 10% of their declared power.

If the driver feels that the losses are greater, then the engine needs. Low compression in the cylinders can occur as a result of wear of the cylinder walls, piston rings, or incomplete closure, etc.

One way or another, any leaks in the combustion chamber will lead to expanding gases breaking out of the cylinder during fuel combustion. This means that the pressure of these gases on the piston will decrease, and the internal combustion engine itself will draw poorly and operate unstably.

Finally, we note that the reason that the car has lost dynamics may not be the engine, but the transmission. In other words, the power unit develops enough power, but it is not fully transmitted to the wheels.

This usually manifests itself in the way that the engine roars, the speed is high, but the car does not move or the acceleration is very slow in lower gears. Often such problems are associated with the clutch or automatic transmission slipping, as well as jamming brake system. To check the brakes, just accelerate the car at smooth road, then engage neutral gear.

If, when coasting, it is noticeable that the car immediately begins to slow down, then the problem is obvious, the wheels are slightly blocked. If no problems with the brakes are identified, then automatic transmission diagnostics are necessary. It is better to entrust this procedure to experienced specialists by delivering the car to a service center.

Poor quality fuel

First of all, you need to blame the fuel - remember where you last refueled - perhaps it’s a new gas station or one whose fuel you have not previously had experience driving with. It is quite possible that the fuel simply turned out to be of very poor quality (it happens that you will simply be lucky if your engine simply stops running - after all, someone’s engine will probably stop starting altogether until the owner completely replaces the fuel in the tank).

If you refuel at the gas station where you usually go, and nothing arouses suspicion, go to local communities in in social networks, the auto club of your region/district, or just a city portal - perhaps the gas station simply had poor fuel delivery.

However, most often, coupled with loss of torque, the incompatibility of the engine with such low-quality fuel also has other symptoms - for example, instability of engine speed, difficulty starting and some others, depending on how bad the fuel turned out to be and on the car model.

But you can most likely determine the poor quality of gasoline yourself by unscrewing the spark plugs from the engine (for this you will need a special spark plug wrench) - in general, spark plugs can often be used as the primary diagnostic method for certain malfunctions in the combustion chamber of the engine, since they work together most closely with this combustion chamber and at the same time are quickly removable. If the fuel contains a large amount of metal-based additives, then the contacts of the spark plug and the “skirt” of the central diode will have a reddish coating (as if red brick had been crushed onto the spark plug).

Dirty air filter

You may also simply have your air filter dirty, and in this case, eliminating the loss of power will probably cost you less than all other options - just replace the air filter - you can either buy it yourself or replace it yourself.

The problem with a dirty air filter is that the fuel-air mixture that enters the combustion chamber of your engine's cylinders does not receive enough air, and therefore the fuel does not burn completely, because a sufficient amount of oxygen is needed for its combustion. The situation turns out to be similar to that of a person with a runny nose - he seems to be eating enough and leading healthy image life, but at certain points in life (during illness with this runny nose), clogged nasal passages do not allow you to breathe normally.

Dirty or old spark plugs

The spark plugs may well be fouled or excessively worn, in which case if the engine is not running because of them, it is also a relatively inexpensive option to fix the problem - simply clean the spark plugs or replace them. However, it should be borne in mind that both periodic contamination and wear of spark plugs is an abnormal process, and the reason for this most likely lies somewhere deeper, or in the spark plugs themselves.

Dirty fuel filter

The fuel filter, like the air filter, can cause a loss of engine power. And the physics of the process here is similar air filter- if in the above case the fuel did not burn completely due to lack of air, then in the case of contaminated fuel filter On the contrary, an insufficient amount of fuel is supplied. In this case it's simple.

Mechanical problems with the engine

If all the above methods did not save you, and the engine still pulls the car poorly, then it’s time to entrust the matter to professionals - stop by good car service and carry out diagnostics of the engine operation - checking the compression (compression ratio in the combustion chambers), for example, can say a lot about the operation of the engine, including the approach to the limit of its resource and the upcoming expensive repairs.

Fuel system malfunction

It is quite likely that the reason for the drop in engine torque is a violation of the normal operation of the fuel supply system to the cylinders, and there may also be a number of reasons why the engine does not gain speed, let’s list the main ones:

Faulty (dirty) fuel pump due, for example, to low-quality fuel or gasoline being sucked out from the bottom of the tank, where most of the foreign dirt particles have settled.
Malfunction of the injector or oxygen sensor.
Leaks in fuel supply hoses or tubes where air is sucked in.

The catalytic converter or exhaust system is clogged

A dirty catalytic converter or line can also cause a decrease in engine torque. exhaust system. In both cases, replacing the corresponding contaminated component will help. It should be borne in mind that the catalyst, as a rule, is very expensive due to the content of noble metals in certain quantities.

We have listed the main and most probable reasons possible loss of engine power - you need to remember that there are a great many such reasons, and if you were unable to establish them yourself, then you definitely need to go to a car service workshop to entrust this matter to professionals.

For the engine to develop full power, the following conditions must be met:

1 - good engine compression;

2 - stable and abundant fuel supply;

3 - a large amount of air.

If one of the above conditions is not met, the engine efficiency will be low.

When traction is lost under load, this means that the engine control unit has entered emergency mode. Emergency mode engine operation is provided for all modern cars. This mode is necessary for the car to reach its destination not quickly, but safely.

To truly find the reason, It is necessary to perform computer diagnostics of the engine.

According to the results computer diagnostics we will understand which direction to move and where to dig in order to find out the true cause of the malfunction.

If diesel the engine does not have enough fuel, then check the fuel equipment: .

If diagnostics show that diesel fuel enough, but the turbine is not blowing enough and there are no errors in the other systems, then it is advisable to measure the engine compression.

Lack of necessary engine compression will result in The engine will not pull and develop full power. If there is no compression of the piston, but there is sufficient air and fuel, then a strong explosion will still not occur, thus there will not be a good exhaust, and as we know, the exhaust spins the turbine, so the turbine will not inflate the required volume of air. Lack of air pressure will result in the car not pulling.

The most common reason for lack of air pressure– problems in the operation of the turbine and shutdown of the turbine itself.

Consider an engine with variable geometry turbines (the most common).

Turbine shutdown usually occurs due to one of two problems: one is related to the air, the other is due to a mechanical failure of the turbine itself (wear of the impellers, play of the axle).

There are variable geometry turbines that are controlled by vacuum, and there are those that are controlled by an electronic actuator.

The car is equipped with four sensors that completely influence the operation of the turbine.

1 - Boost pressure sensor. It will measure the air pressure in the intake manifold.

2 – Boost pressure regulator. This is the valve that controls the geometry, i.e. turns the turbine on and off.

3 - Temperature sensor intake air. Shows the temperature of the air entering the motor.

4 – Atmospheric pressure sensor. Measures the atmospheric pressure where the vehicle is moving (normal atmospheric pressure relative to sea level).

Most often, it happens that the air intake system in the car is broken. Thus, the turbine drives all the air out (the pipe is torn, there is a poor connection at the joints, the intercooler (air cooling radiator) is cracked).

To identify similar problem it is necessary to check all intake system air for tightness.

The next most common problem is: Faulty geometry in the turbine.

To check the geometry on a car, you need to remove vacuum hose from the actuator on the turbine itself. Put another hose on it and try it with your mouth or special device suck in air. After this procedure, the rod that controls the geometry must change its position. If it does not change its position, then there may be 2 reasons: either the membrane in the actuator is torn, or the geometry itself is jammed.

Failure of the boost pressure regulator and boost pressure sensordetected by the presence of errors in them in the results of computer diagnostics.

The boost pressure regulator can also be checked with a vacuum gauge.

Don't forget to check Vacuum pump and vacuum tubes throughout the machine for leaks. This is done as follows: disconnect the pipe in some place, apply your hand, you should feel air being drawn in.

A turbine with an electronic actuator can only be checked using computer diagnostics!

Please note that the loss of traction can also be affected by "swirl" flaps (not available on all cars).

We hope that this information will help you identify the reason why your car does not pull or does not gain full power, and also gain enough knowledge to communicate with car service specialists.

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