The car does not pull uphill and twitches. Why doesn't the car accelerate and pull? List of possible causes. The main reasons for the lack of engine dynamics

In general, the engine can stop pulling for a variety of reasons - this is one of the most common malfunctions, which can have a huge variety of reasons, and below we will consider the most likely ones, describe their symptoms and investigate this issue in detail. Indeed, one day something can happen to each of us that the engine will lose power, without being accompanied by any more symptoms. The engine probably does not show any clear signs of any illness, it seems to be almost in perfect order and does not emit any unusual noises and vibrations, but at the same time it simply does not pull as well as it usually does. And the problem seems to be getting worse and worse every day, although you probably didn't even notice when the motor first began to pull worse.

If you are familiar with this situation, then let's consider the following reasons for reducing the thrust of the motor:

Low-quality fuel

First of all, you need to blame the fuel - remember where you last refueled - perhaps this is a new gas station or one with which you previously did not have driving experience. It is quite possible that the fuel just turned out to be of very poor quality (it happens so much that you are just lucky if your engine just stops pulling - 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 do, and nothing arouses suspicion, go to local communities on social networks, a car club in your region / district or just a city portal - perhaps the gas station simply had a bad delivery of fuel.

However, most often, coupled with a loss of thrust, the incompatibility of the engine with such low-quality fuel has other symptoms - for example, instability of engine speed, difficulty starting and some others, depending on how bad the fuel was and on the car model.

But it is most likely to determine the poor quality of gasoline yourself by unscrewing the candles from the engine (this will require a special spark plug wrench) - in general, candles can often be used as a primary diagnostic method for certain malfunctions in the engine combustion chamber, since they are the ones who most closely cooperate with this combustion chamber and at the same time are quick-detachable. If the fuel contains a large amount of metal-based additives, then the contacts of the candle and the "skirt" of the central diode will have a reddish coating (as if a red brick had been crumbled into a candle).

Dirty air filter

Your air filter may also just get dirty, and in this case, eliminating the loss of power will cost you, perhaps, cheaper 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 air-fuel mixture that enters the combustion chamber of your engine's cylinders does not get enough air there, and therefore the fuel does not burn completely, because it needs a sufficient amount of oxygen to burn it. It turns out a situation similar to a person's runny nose - he seems to eat enough and leads a healthy lifestyle, but at certain moments of his life (during an illness with this runny nose), clogged nasal passages do not allow breathing normally.

Dirty or old spark plugs

Spark plugs may well be dirty or excessively worn, in which case if the engine is not pulling due to them, it is also a relatively inexpensive option for troubleshooting - just clean the plugs or replace them. However, it should be borne in mind that both periodic pollution and wear of spark plugs are abnormal, and the reason for this lies, most likely, 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 to the air filter - if in the above-described case the fuel did not completely burn out due to lack of air, then in the case of a dirty fuel filter, on the contrary, insufficient fuel is supplied. In this case, simple.

Mechanical problems with the engine

If all the above methods did not save, and the engine still pulls the car badly, then it is time to entrust the job to professionals - go to a good car service and diagnose the engine's operation - checking the compression (compression ratio in the combustion chambers), for example, can say a lot about work engine, including the approach to the limit of its resource and the upcoming expensive repairs.

Malfunction in the fuel system

It is quite probable that there is such a reason for the drop in engine torque as a disruption in 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 pick up speed, let's list the main ones:

Defective (dirty) gasoline pump due, for example, to low-quality fuel or suction of gasoline from the bottom of the tank, where most of the foreign dirt particles have settled.
Defective injector or oxygen sensor.
Leakage of hoses or fuel pipes where air is sucked in.

Clogged catalyst or exhaust system

A dirty catalytic converter or exhaust line can also cause a decrease in engine thrust. 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 because of the content in it in certain quantities of noble metals.

We have listed the main and most probable reasons for a possible loss of engine power - you need to remember that there are a great many such reasons, and if you did not manage to install them yourself, then you must definitely go to a car service workshop to entrust this business to professionals.

Often beginners and not only drivers are interested in why the car does not accelerate and pull. Typically, this problem is related to the engine. At the first signs of a malfunction, it is advisable to conduct a detailed diagnosis of the engine. This will save you from a long search for a breakdown. Almost anything can cause a motor to lack thrust.

Owners of new cars often encounter this. If diagnostics fail to identify the problem, then you will have to suffer a little. This is connected and will pass to a run of 5000 km. Most often this is found in models of components that are assembled in China.

Wear of parts

Why doesn't the car accelerate and pull? In some cases, this may be due to a high level of engine wear. Usually seen on fairly old machines. Most often, the rings suffer, in connection with this, the compression falls. Therefore, the first thing to do when reducing power is. If even in one cylinder the indicator is less than 11, then the engine will have to be overhauled.

Sometimes a decrease in engine power indicates the presence of carbon deposits on the valves; this can only be checked by removing the cylinder head. Indirect signs:

Change in the ratio of gases in the exhaust;
Burning on the panel "check".

To eliminate it, you will have to clean the valve. After this work, everything should be normalized.

Filters

Often the car jerks due to lack of fuel... Fuel filters are installed in every car. There are usually two of them. The coarse filter is either in the fuel pump, or it is embedded in the hose. A fine post-treatment filter is installed in front of the injector. If any of these cleaners are clogged, fuel cannot enter the injector sufficiently. This, in turn, dramatically reduces the efficiency of the car.

In the summer often air filter clogged... In this case, the mixture is poorly enriched with oxygen, and the fuel does not burn completely. As a result, there is a loss of power again. To avoid such problems, you need to replace the filter elements in a timely manner.

Ignition

A modern engine is quite sensitive to ignition work. Incorrect spark plug electrode gap can cause engine failure. And, accordingly, to a decrease in engine power. Therefore, always. You also need to check their performance at a special stand. It can also be done in a simple but reliable way.

For this, the candle is unscrewed. A high-voltage wire is put on it, after which the engine is cranked with a starter. The quality of the spark is determined visually. It should be white and blue. If the spark is red or yellow, it is considered poor quality. Look for a problem in the ignition system. This is most likely the reason for the loss of power.

Diagnostics

For a more precise definition of the problem, it is desirable. This procedure will help identify sensor and power problems. To do this, you need a laptop with a special program. Having deciphered the readings, you need to start troubleshooting. Most often, the reasons may be as follows:

Malfunction of the crankshaft position sensor. With this malfunction, the "Check engine" is usually lit. A decrease in power occurs due to a mismatch between the impulse supplied to the engine control unit and the real position of the crankshaft. As a result, incomplete combustion of fuel occurs, and the efficiency of the motor decreases;
... This problem can also affect engine power;
The reason may be due to. In this case, the check will not light up. Therefore, in any case, it is necessary to carry out diagnostics.

Conclusion... As you can see, there are enough reasons for the problem and they are all quite diverse. Offhand to say why the car does not accelerate and pulls will not be able to any auto repairman. In any case, you will have to carry out thorough and painstaking work to diagnose and search for the causes of the malfunction.

As a rule, during the long-term operation of a vehicle, almost every driver sooner or later notices that the engine pulls poorly. In other words, the power unit can hardly cope with the loads, there is a loss, the unit needs to be rotated to high revs to maintain the usual pace, the car accelerates worse from a standstill, slowly picks up speed, etc.

Moreover, the motor in many cases runs smoothly, does not troit, no knocking or noise during operation. Immediately, we note that there is a fairly wide list of possible reasons why a warm engine does not pull, there is a loss of engine power when cold and / or 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 thrust of the power unit.

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

So, if no other symptoms, besides the loss of traction, are found, then it is immediately necessary to pay attention to the quality of the fuel, the serviceability of the system, etc.

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

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

Usually, such manipulations are necessary when, in parallel with the loss of thrust, an unstable operation of the internal combustion engine is noted, and under load, the engine starts poorly, on the panel, etc.

Also, owners of gasoline engines can independently determine the quality of gasoline. To check the spark plugs must be unscrewed from the engine. Violation of the combustion process of the fuel-air mixture in the cylinders, as well as the presence of impurities in the fuel, can be detected by the soot on the spark plugs and its color.

For example, if the fuel contains many third-party metal-containing additives and additives, then the skirt and electrodes may become covered with reddish carbon deposits (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 drop 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 "headroom" for further acceleration.

The candles can be dirty, and it should not be ruled out that their resource has come to an end. To fix this problem, you can make or immediately replace the entire kit with a new one.

It is important to take into account that if the new spark plugs are correctly selected for a specific engine in terms of the heat rating and other parameters, but they still quickly become dirty, then the reason for the loss of thrust is not in them. Carbon deposits in this case indicate problems with mixture formation or combustion of the fuel charge in the cylinders.

If everything is in order with the candles, then it is necessary to check the condition of the fuel and air filter. In the first case, insufficient throughput can lead to the fact that the required amount of fuel is not supplied to the cylinders to prepare the so-called "power" mixture.

As a result, the engine loses power, that is, it does not pull under loads. In such a situation, it is sufficient to replace the indicated 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 air / fuel mixture.

This leads to the fact that fuel without a sufficient amount of oxygen burns out incompletely. Engine power in such conditions naturally drops, carbon deposits form in the combustion chamber, candles become heavily soiled, etc. It also needs to be replaced to fix the problem.

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

While spark plug and filter problems can be identified on the road, more serious power and ignition problems are much more difficult to diagnose and fix on the spot. 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 and or the injector.

Let's focus on the more common electronic injection. In the list of the main malfunctions of modern injection internal combustion engines, there are:

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

If we talk about the ignition system, in addition to the spark plugs, you should also check the ignition coils, etc. With regard to fuel delivery, at the initial stage, the pressure in the fuel rail (rail) should be measured. In parallel, the fuel rail pressure regulator is also checked.

Often, on many cars, problems are associated with the fuel pump, which is located in the gas tank, as well as with the specified regulator. To measure the 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 both the gas pump and the pressure regulator may be the culprit.

The regulator's task is to discharge excess fuel into the return line at a time when the pressure is above normal. If the settings are lost or the regulator itself leaks or is faulty, then the fuel will be discharged into the return line ahead of time. To check this, air is pumped in by a compressor or pump, the pressure in the rail increases. If the regulator is triggered before the recommended pressure, the element needs to be adjusted or replaced.

Other causes of reduced engine output

The condition of the motor also has a great influence on the power of the motor. The fact is that to protect the environment from harmful emissions during the operation of the internal combustion engine, catalytic converters are installed in the exhaust.

During operation, the filter catalyst may collapse, reducing the throughput of the exhaust system. As a result, the engine is "suffocated". 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 a 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 “cheated” by software or other available methods.

Also, with a decrease in engine power, it is necessary to separately check it to exclude the possibility of a valve timing failure. Sometimes there are situations when the belt can jump by one tooth, the chain is stretched, etc.

In this case, the synchronous operation of the valve mechanism in relation to the strokes of the internal combustion engine may be violated. This leads to various failures, unstable operation of the unit and a decrease in power.

We also add that engine wear and certain malfunctions also affect engine power. As a rule, worn-out, used internal combustion engines usually lose about 10% of the declared power.

If the driver feels that there are more losses, then the engine is needed. 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 the fact that the expanding gases during the combustion of the fuel will burst out of the cylinder. This means that the pressure of these gases on the piston will decrease, and the ICE itself will pull poorly and work unstably.

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

This usually manifests itself in such a way that the engine roars, rpm is high, but the car does not move, or acceleration is very slow in low gears. Often such problems are associated with the clutch or slippage of the automatic transmission, as well as with the wedging of the brake system. To check the brakes, it is enough to accelerate the car on a flat road, then engage in neutral gear.

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