No engine thrust reason. Why the diesel engine does not pull or the reasons why the engine does not develop full power. Specific engine faults

All other things being equal, any engine produces the specified performance characteristics, provided that the air-fuel mixture is properly mixed, forgive the tautology. That is, a mixture of gasoline (or diesel fuel) with air in the correct ratio. Accordingly, the tank should be filled with, say, fairly clean diesel fuel with the correct cetane number. Or corresponding to the necessary octane number petrol. Otherwise, detonation is possible even at the latest ignition timing.

Similar problems can arise simply due to a clogged fuel filter or coked injectors. But first things first. So, what are the main causes of loss of traction?

The easiest way is to check first air filter, which in our conditions should be changed more often than the interval recommended by the manufacturer. When the air filter is clogged, the engine control unit automatically reduces the fuel supply, resulting in a drop in engine power.

Next, suspicion usually falls on the spark plugs (although they may not be to blame) and ignition coils, which provide the electrical impulse necessary for ignition. Problems with them are usually accompanied by the fact that the engine “troubles” and does not produce the required power.

The engine also does not pull due to a worn timing belt or a chain that has jumped a couple of teeth. Because of this, the gas distribution cycles are disrupted, the cylinders are filled with a non-optimal mixture and, as a result, power drops.

Older cars often lose power due to cylinder wear. piston group. Worn cylinders do not allow maintaining a given compression without providing the proper degree of compression of the air-fuel mixture.

It may not pull at all new engine- in the cold season, when unheated operating temperature viscous oil resists the movement of all engine mechanisms. This also happens in warm weather due to a faulty thermostat.

A faulty exhaust system also negatively affects power performance. It needs to be cleaned periodically to remove carbon deposits. Exhaust system pipes are bent or clogged catalytic converter also reduce power.

In addition to near-engine troubles, a worn clutch can play a cruel joke on recoil. It will simply slip when you try to press the gas pedal harder, but this can be easily understood by the floating speed when changing gear.

Might grab it too braking system, which is why experienced motorists usually put the car in gear in winter so that parking brake didn't pick up the ice.

Of course, you should regularly check the tire pressure: flat tires do not contribute to dynamic acceleration. A worn transmission, especially an automatic one, in turn negatively affects performance.

However, there can be many reasons; they can complement each other, aggravating the situation with cravings. For example, there are many reasons for a turbocharged engine to lose power. The turbocharger wears out intensively, especially with active drivers. There may be problems with the tightness of the turbine and compressor lines. Or simply a mechanical malfunction of the turbocharger...

Often, beginners and other drivers are interested in why the car does not accelerate or pull. Typically, this problem is related to the engine. At the first sign of a malfunction, it is advisable to carry out detailed diagnostics engine. This will save you from a long search for a breakdown. Almost anything can cause a lack of traction in the engine.

Owners of new cars often encounter this. If diagnostics fail to identify the problem, you will have to suffer a little. It is connected and will last for 5000 km. This most often occurs in models for which components are assembled in China.

Wear of parts

Why doesn't the car accelerate or pull? In some cases this may be due to high level engine wear. Usually seen on fairly old machines. Most often, the rings suffer, and as a result, compression decreases. Therefore, the first thing to do when reducing power is. If in at least one cylinder the indicator is less than 11, then you will have to do major renovation engine.

• Changing the ratio of gases in the exhaust;
• The "check" is lit on the panel.

Filters

The car often jerks due to lack of fuel. Each car is equipped with fuel filters. Usually there are two. The coarse filter is either located in the fuel pump, or it is embedded in the hose. A fine filter is installed in front of the injector. If any of these cleaning devices become clogged, fuel cannot reach the injector in sufficient quantities. Which in turn dramatically reduces the efficiency of the car.

Ignition

A modern engine is quite sensitive to ignition operation. An incorrect gap on the spark plug electrodes can lead to failures in engine operation. And, accordingly, to a decrease in engine power. Therefore always. You also need to check their performance on a special stand. This can also be done in a simple but reliable way.

To do this, the candle is unscrewed. A high-voltage wire is placed on it, after which the engine is cranked with the 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. You should look for a problem in the ignition system. Most likely, this will be the cause of the loss of power.

Diagnostics

For a more precise definition of the problem, it is advisable. This procedure will help identify problems with sensors and power system operation. To do this, you will need a laptop with a special program. Having deciphered the readings, you need to begin troubleshooting. Most often, the reasons may be the following:

• Malfunction of the crankshaft position sensor. With this malfunction, " Check engine" The reduction in power occurs due to a mismatch between the pulse supplied to the engine control unit and the actual position of the crankshaft. As a result, incomplete combustion of the fuel occurs, and the engine efficiency 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. No auto mechanic can tell offhand why the car doesn’t accelerate or pull. In any case, you will have to carry out careful and painstaking work to diagnose and find the causes of the malfunction.

Probably, any driver has encountered such a problem when the car has lost its former dynamics: it takes a long time to accelerate, and when climbing, it completely refuses to move in higher gears. In this article we will tell you in detail what to do if the VAZ engine does not pull or pulls poorly, we will look at the main causes and troubleshooting methods.

Conditionally all types gasoline engines can be divided into gasoline and injection. In general, their principle of operation is absolutely the same, but the factors that affect engine power become different. Let's consider the problem of carburetor and injection engine separately.

VAZ carburetor engine does not pull

The carburetor is mechanical device, intended for a mixture of air and gasoline, with further supply of this mixture into the combustion chamber of the engine. Problems with a lack of engine power at the carburetor are quite common and there are many reasons for them. We will try to deal with each one.

• Engine power system

First of all, the loss of engine power may be hidden behind the power system. As a rule, the engine does not pull due to a lack or excess of fuel. The fact is that gasoline and air are mixed in a certain ratio. And if one or another element is missing, the motor will begin to work unstably and will stop developing the required power.

The ratio of air to fuel should be within 15 to 1. If the amount of gasoline exceeds the permissible parameters, then it will not burn completely, which means it will reduce engine response. In addition, such a change in ratios will seriously increase fuel consumption and subsequently lead to other engine malfunctions.

An insufficient amount of fuel even leads to “starvation”. The ignition of the air-fuel mixture will be insufficient and the piston will move slowly. All this is achieved correct setting carburetor, precise selection of jets and many other factors.

It starts with the selection of jets. An important condition is to have a larger nozzle for air than a nozzle for gasoline. Then it undergoes adjustment float chamber carburetor, which should be only half filled with gasoline. After this, the car engine starts and the quantity and quality of fuel is adjusted in accordance with the technical literature on this model carburetor If, at the same time, a stable speed is achieved within the range of 800-900 rpm, then the carburetor adjustment was successful.

Another link in the food system is the presence of clean air and fuel filters. If the filters are too dirty, then fuel or air will pass through with great difficulty, which also disrupts the composition of the mixture. Therefore, filters must always be kept clean.

Check also. It is possible that it does not open completely. In this case, stop the engine and adjust the throttle position.

It is also quite possible that the fuel pump has stopped creating the required pressure. To do this, you need to remove it and check it. It is quite possible that the drive and its diaphragm will have to be changed. There is another very common malfunction - increased wear of the fuel pump rod. This means that when manually it pumps perfectly, but when you start the engine it works for a short time, then it loses power and the engine stalls.

• Valve assembly

The gas distribution mechanism also plays an important role in maintaining engine power. If the valves, due to wear, have lost their tightness, then gases will break through from the combustion chamber directly into the valve mechanism. All this reduces the pressure created in the engine cylinders, so the pistons move noticeably slower.

To restore the tightness of the valves, it is necessary to grind them in and adjust them correctly. The essence of the adjustment is to set the thermal gaps in their impact mechanism. The size of the gaps is indicated in the reference literature for the car engine.

In addition, the valve train must operate in synchronization with the engine crankshaft. If the opening and closing of the valves does not correspond to the position of the piston, the engine will not only pull poorly, but may not start at all.

• Ignition system

Perhaps the decisive factor. Sparking must occur only in strictly specified cycles, otherwise the motor will not only pull poorly, but may also overheat and operate very, very unstable. If the adjustment of the OZ was successful, but the motor still does not pull, but idle speed It works completely unstable, which means it makes sense to check the ignition system as a whole.

On contactless system ignition, you need to make sure that the switch is working properly. To do this, turn on the ignition and monitor the position of the voltmeter needle: first it should deviate to 12 Volts, and after a second it should rise even higher. If the Voltmeter is not provided by the design of your car, then replace the switch with a known good one and check the ignition operation again.

First of all, pay attention to the cleanliness and tightness of the contacts in the distributor. If everything is in order, you can move on. Start the engine and pull out one by one high voltage wires. After each wire, listen to how the motor operates. If it starts to work even worse, then there is a spark in this cylinder. If the engine operation has not changed, this means that you have found a faulty spark plug or high-voltage cable. This assumption can be verified by replacing the element with a known good one.

Incorrect use of spark plugs also affects engine performance. Most often, the difference between spark plugs lies in the gaps between the electrodes. The gap size must correspond to the engine, the season of operation of the vehicle and the spark plug model.

Check the ignition distributor. It is quite possible that a resistor located in the rotor circuit burned out. Another problem is the loose fit of the contact carbon. Try replacing it or the spring.

The last ignition problem is the unclear operation of the octane corrector. If there is no required vacuum, the special plate does not return to initial position. In addition, there is increased play in the system. Fix it and replace any faulty parts. Check the hose for leaks.

The last and most terrible malfunction is this. These elements are designed to reduce friction of the piston against the walls of the engine cylinder and remove residual oil so that it does not enter the engine combustion chamber.

Failure of the rings entails a violation of the tightness of the combustion chamber, and therefore the cylinder compression is seriously reduced. This can be determined by increased consumption oils and corresponding color exhaust gases. In this case, only serious engine repair will help.

• Faulty exhaust system

The exhaust part of the car also plays an important role in creating the required pressure in the engine cylinders. If this pressure difference between the inlet and outlet is disturbed, the engine thrust may noticeably decrease. In this case, check whether the exhaust system is dirty: the pipes must be removed and inspected. Special attention pay attention to the exhaust pipe. If there are any holes in it, it will lose its seal and become unusable.

If there are any extra holes or damage in the resonator, pipes or muffler, they must be replaced without fail.

The injection engine pulls poorly

Part of the faults carburetor engine can be safely attributed to injection malfunctions. This applies to the timing mechanism, filters, ignition system, exhaust and engine piston group.

• Gasoline pump malfunction

The main feature of the injection engine is the presence of an electric gasoline pump. He is Electrical engine, which creates a vacuum and pumps fuel system required amount of fuel.

Affects the stability of engine speed. After all, if it works intermittently, then gasoline will be supplied in the appropriate quantity. Most often, the electrical wiring, fuel pump relay or contact Group electrical circuit. In this case, it is necessary to diagnose and repair the faulty fuel pump.

Another problem with the fuel pump is increased contamination of its filter. Measure the outlet pressure and compare it with the normalized values. If the measurement result does not correspond to the reference values, the fuel pump filter must be cleaned.

• Nozzles (injectors)

A nozzle is called a small solenoid valve, which at certain times sprays the air-fuel mixture into the combustion chamber of the engine. Engine power also depends on the correct operation of the injectors.

Diagnosis of their serviceability is carried out using a multimeter. To do this, you need to check the resistance of the windings for open circuits and short circuit. If a malfunction is detected, the injectors must be replaced.

• Faulty sensors

Sensors are the main collector of information for work electronic unit management. If one of the sensors malfunctions, the controller, without receiving necessary information, instantly puts the motor into emergency mode with the corresponding lamp turning on dashboard engine.

A faulty sensor can be identified by performing electronic diagnostics at the station Maintenance and replace.

• Malfunction of the ECU itself

The electronic control unit may also malfunction. To check its performance, you need to replace it with a known good one and check the operation of the engine. The voltage supplied to the unit should be 12 Volts.

Video - The engine does not pull at low speeds, the car does not go uphill

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 listed conditions is not fulfilled, then 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.

Let's consider an engine with variable turbine geometry (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 - Intake air temperature sensor. 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 such a problem, it is necessary to check the entire air intake system for leaks.

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

To check the geometry on a car, you need to remove the vacuum hose from the actuator on the turbine itself. Put another hose on it and try to suck in air with your mouth or a special device. 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 has broken, or the geometry itself has 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.

We must remember to check the 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.