What to do if the engine does not spin up?

27.08.2020

Traffic regulations online When operating a car with a gasoline or diesel engine, sometimes a situation arises when the expected increase in speed does not occur when you press the accelerator pedal. Serviceable power unit must instantly respond to an increase in the combustible mixture in the combustion chambers by increasing the speed of rotation crankshaft

, but if this does not happen, you need to look for a fault. Its cause can be either fairly simple and easily fixed things or serious breakdowns.

The main reasons for the lack of engine dynamics A driver who constantly operates a car can easily detect deterioration dynamic characteristics engine, which manifests itself in sluggish acceleration, bad traction

, increased fuel and oil consumption. These processes are often accompanied by the appearance of bluish or black exhaust. Most often this is due to the following reasons:
Insufficient heating of the power unit.
Poor quality of fuel used.
Clogged air filter and malfunction of the air supply system.
Problems with the gas distribution mechanism.
Malfunctions of fuel supply systems.
Sensor malfunction.
Ignition system malfunctions.
Weak compression in the cylinders.
Incorrect operation of the vehicle's ECU.

Specific malfunctions of engines with a turbocharger or carburetor.

Cold engine The dynamic characteristics of the power unit will not reach their maximum until working temperature the coolant will not rise to 90 o C. Cold engine

is unable to quickly develop speed; for this, the air-fuel mixture in the combustion chamber must be heated. Otherwise, the engine will stall, jerk and detonate.

Fuel quality Usage quality gasoline piston group.

Filter contamination

An excessively clogged air filter reduces the amount of air that can pass through it into the combustion chambers, causing the engine to lose power and run rough. A similar consequence is caused by a lack of fuel flow into the combustion chambers when the fuel pump malfunctions or it is difficult to pass through the line or through fuel filters for various reasons.

Malfunction of the gas distribution mechanism

Breakdowns or incorrect adjustment of the gas distribution mechanism shifts the gas distribution phases from the optimal point and causes a sharp decrease in engine power. This occurs due to incomplete release of the cylinders from exhaust gases, or insufficient filling with air or air-fuel mixture. If the timing chain or belt jumps one or more teeth, it disrupts the operation and adjustment of the mechanism that provides the required ignition timing depending on engine speed. A significant drop in power is also observed when the timing valves are incorrectly adjusted, when they are insufficiently opened or not completely closed.

Fuel system malfunctions

When there is a problem with the power supply system of a gasoline engine, the loss of power is felt first. These include clogging fuel filters, interruptions in the operation of the fuel pump, power supply to the injectors and depressurization of the fuel line, due to which the engine feels a lack of fuel. In diesel engines, the most common problems with fuel equipment are wear of the injectors and fuel pump, depressurization of the fuel line, freezing of fuel in the fuel line and clogged filters.

Sensor malfunctions

IN modern engines To achieve a combination of high dynamics and low fuel consumption, the readings of various sensors are used to determine the position of the crankshaft, air flow, detonation in the combustion chamber, the composition of the exhaust gases, the position of the air and throttle valves, and external temperature. Data from them enters the engine ECU and affects its operating mode. The malfunction of one or another sensor makes the operation of the power unit less than optimal, which manifests itself in a loss of power.

Ignition system malfunctions

Most often, problems in the ignition system that reduce engine power relate to spark plugs, in which the gaps between the electrodes may be broken, carbon deposits have occurred on them, or the insulator may be damaged. Deterioration in the quality of the spark or its absence is often the result of a break, broken contacts or integrity high voltage wires, ignition coils and distributor.

Piston group wear

During long-term operation of the engine, natural wear of the piston group occurs, which causes a drop in the required compression in the cylinders and the power of the power unit. Excessive wear can occur when the piston rings are stuck due to improper operation of the engine, the use of low quality fuel and oil.

Problems with the computer

Management of all work processes modern car carries out the electronic unit, which collects sensor readings and, based on the program embedded in it, regulates the operation of the engine. The operation of the ECU can be changed by setting different operating modes depending on the required flow rate and type of fuel used, vehicle operating conditions and other characteristics. Malfunctions in the operation of the electronic unit or its incorrect settings can lead to both loss of power and the inability to operate the engine itself.

Specific engine faults

Old car models with a carburetor are still quite actively used by domestic car enthusiasts. Failure of various components of such power systems manifests itself in a noticeable drop in engine power and has the following characteristic malfunctions:

Fuel pump failures causing a drop in pressure in the system.
Dirt gets into the carburetor, which clogs the jets and causes problems with the operation of the needle valve.
Incorrect adjustment of the composition of the combustible mixture.
Malfunctions in the operation of the carburetor dampers and economizer valve.
Incorrect float operation.

Some models of new engines have one or more turbines that pump air into the combustion chamber, thereby increasing the number Horse power, which the power unit is capable of delivering. Breakdowns or disruptions in their operation are caused by a sharp drop in the throttle response of the power unit.

A drop in engine power should be the reason for vehicle diagnostics to identify the malfunction and completely eliminate it. It’s good if the cause of loss of dynamics turns out to be such easily removable reasons as low-quality fuel, clogged filters or old spark plugs. But malfunctions in the operation of the gas distribution mechanism, wear of the piston group and other more serious problems require immediate repair, as they can lead to significant damage and significantly higher monetary costs.

One of the signs of engine failure is usually that the engine does not gain speed ("does not spin up" as many motorists say). There can be many reasons why the engine does not pick up speed well; only an experienced diagnostician can make an accurate diagnosis, but the initial check can be carried out independently. So, what are the reasons for the engine not revving up?

The engine does not gain speed. What to check first?

Fuel supply system. Usually, checking the reasons why a gasoline or diesel engine does not gain momentum begins with this. If we are talking about a gasoline engine, then first of all you should check the serviceability of the gasoline pump - it does not matter whether it is mechanical or electric.

For diesel engines, the check begins with the equipment with injectors, because it is this that most often causes the engine to lose power. In addition, the possibility of air leaks into the fuel system.

Both gasoline and diesel engines have this problem because it could become clogged and affect engine traction.

Ignition system. First, check if the engine is shaking. Then remember if the timing belt or chain has been replaced recently. Very often, the timing belt or chain is installed incorrectly, which is why the engine does not pick up speed and becomes “stupid.”

In addition, you should carefully inspect the wires and spark plugs to ensure their integrity and serviceability. Engine thrust can also be affected by a failed sensor (mass air flow sensor, air flow sensor, crankshaft sensor, camshaft sensor, position sensor throttle valve etc.).

Air supply. Another common reason why an engine does not pick up speed is air leakage along the path of the fuel-air mixture into the cylinders. In addition, it follows.

Exhaust system. In many cars, traction is noticeably affected, so check exhaust system It’s worth starting with the catalyst (if you have one).

Another very common reason why an engine won't rev is bad fuel. If you refuel at an unknown gas station, the problem may be with the quality of the fuel.

If all of the above is normal, then for a more detailed study it is better to contact specialists who can accurately determine the cause of the malfunction.

It is important for every motorist that he vehicle worked properly, and was able to develop its own optimal power without any problems. However, for a number of reasons, the power unit of the machine may, over time, stop gaining the number of revolutions required for its normal operation. In this case, the car will lose its former agility, and its traction qualities will decrease significantly.

Symptoms of a problem

Determining the lack of revolutions is quite simple and every driver is able to distinguish the normal power of his car. A decrease in power is always accompanied by a deterioration in dynamics, traction, weak acceleration, and also an increased internal combustion engine. Often, a car with this problem consumes much more fuel, and the exhaust gases may be black in color.

A serviceable engine always reacts without delay to pressing the accelerator pedal and begins to develop more revolutions. If this does not happen or no noticeable difference is observed, then attention should be paid to both the engine and the fuel system.

As for the malfunctions due to which the power unit is not able to gain the required number of revolutions, it is worth noting that there are quite a lot of them.

Insufficient heating of the internal combustion engine

First of all, it is worth understanding that cold engine unable to fully function. For this reason, before starting to drive, it is recommended to let the unit idle for several minutes or start driving on a cold engine without rapid acceleration. But it is worth remembering that if the car is equipped carburetor engine, then it is better to give preference to warming up rather than a gentle start. Otherwise, movement may be jerky and the engine may stall.

If this system fails, then on our own You won’t be able to get by and you should definitely visit a car service center.

Carburetor engine

In the case of a carburetor, everything is somewhat simpler - the angle is set exclusively manually, turning the ignition distributor. It is quite difficult to install it correctly, but still possible.

If ignition of the mixture occurs when the piston is at the top dead center, then an explosion of the mixture will occur when it begins to move downwards. To prevent this from happening, the ignition angle is adjusted. To correctly set the angle, it is necessary to identify the compression stroke in the first cylinder. To do this, you can take a piece of cotton wool and plug the hole in the cylinder spark plug. After this, the crankshaft is rotated by the ratchet and when compression begins, the fleece will fly out under pressure. In this case, the marks on the pulley and the front cover must correspond to each other. When the marks come together, it is necessary to pay attention to the distributor rotor, it should be directed specifically at the contact of the first cylinder (the numbering of the cylinders is indicated on the distributor cover). If everything is exactly like this, then everything is in order with the ignition timing.

Next, if an error is detected, it is necessary to loosen the lower nut securing the distributor. After that, slightly lifting the distributor, you should rotate the rotor until it comes into contact with the first cylinder. After installing the rotor, the fixing nut can be tightened, but not completely.

Now you need to adjust the ignition angle. This is done as follows. The tester or test lamp is connected to positive terminal ignition coils and to the vehicle ground. The ignition is turned on and the setup begins. To do this, press the rotor with one hand and slowly turn the vacuum regulator clockwise with the other until the control lamp goes out. Afterwards, the distributor body is rotated in the opposite direction until the lamp ignites or a reading is detected on the tester. Once this has happened, turning is completed and the nut is tightened tightly. Thus, the ignition timing on carburetor engines is adjusted.

Gasoline level in the carburetor float compartment

During the formation of the air-fuel mixture, the fuel limit is float chamber The carburetor plays a huge role. If the level is too low, the amount of gasoline in the mixture decreases noticeably, as a result of which the internal combustion engine is unable to develop sufficient power. When the level is high, the fuel mixture is enriched, but it is unable to fully warm up before entering the cylinder, which is why the engine speed also decreases.

In order to adjust the fuel level, it is enough to bend the float mount in the desired direction and to the required limit.

Problem with the accelerator pump and clogged lines

When diagnosing, it is important to pay attention to the condition of the accelerator pump, because it is thanks to its reliability that the engine responds to pressing the accelerator pedal. In normal condition, the jets located in the pump should supply fuel in a thin stream.

It's quite easy to check. Needs to be dismantled air filter to open the view of the first camera. After this, you should open the throttle valve and hold it in this state for several seconds. As a result, a powerful and thin jet of fuel will come out of the nozzle, which should be directed clearly into the second chamber. If the stream is weak or uneven, the nozzle is clogged and requires urgent cleaning.

Air leak in the intake manifold

Among other things, the cause of a significant drop in the speed of the power unit can also be a normal air leak in the intake manifold. At the same time, the engine starts poorly, stalls, gasoline consumption increases, and problems arise even at Idling. This is due to the fact that in fuel mixture additional air penetrates.

It is quite difficult to find out that the injection unit has stopped developing full speed precisely for this reason, and it is even more difficult to find the very place where air is leaking. This most often occurs due to wear of the manifold gasket. To check, you can generously cover the junction of the manifold with fuel using a syringe along the entire perimeter of the connection. Next, you should start the engine and if you can develop normal speed, then the problem lies here.

However, it is worth understanding that this method is quite primitive. For a complete diagnosis intake manifold It is recommended to visit a car service center, since it is very difficult to do this on your own.

Disturbance of gas distribution

When the timing belt breaks, the valve timing in the unit is disrupted. This also happens after replacing it, if new belt was installed with the crankshaft and camshaft gears offset by at least one tooth. In this case, the operating cycle of the internal combustion engine is disrupted, fuel consumption increases, and the exhaust also acquires different colors due to incomplete combustion of the mixture.

Due to the fact that replacing a belt requires certain knowledge of engine operation, entrust this procedure to better car service, rather than trying to set the cycle yourself.

Low compression

Perhaps the most serious problem due to which engine power decreases - decrease.

This happens when parts of the piston group wear out. The consequence of this problem is the loss of energy during operation of the internal combustion engine. Compression is checked with a compression meter, and if the readings are below optimal, then this problem requires mandatory overhaul engine. Compression is considered to be within the range of 10 - 14 kg/cm2, but it is different for each car and is indicated in the documentation.

October 14, 2017

The most unpleasant type of problem is when something in the car is half broken. In such cases, troubleshooting turns into a difficult task, reminiscent of catching fleas. A common example: the engine does not gain speed after pressing the accelerator pedal. The car drives, but is not able to accelerate to normal speed - the engine “sneezes” and stalls. If you decide to find the problem yourself, check out full list reasons causing inadequate behavior of the power unit.

Fuel system problems

If you are faced with a problem with a drop in engine power, start looking for a problem with the fuel supply system. After all, if the engine does not respond to opening the throttle or begins to stall, it is logical to assume that it simply does not have enough fuel. Your actions:

Remember when the fine filter was changed and check its condition. A clogged filter element does not allow enough gasoline to pass through, which is only enough for idling without load.
A common cause is a fuel pump strainer located in the tank clogged with dirt. Often, car enthusiasts ignore its replacement, installing only new filter. To check the coarse mesh, you will have to disassemble the gas tank and pull out the pump.
The pressure bypass valve, which dumps excess fuel back into the tank, has failed. It is checked by measuring the pressure in the fuel rail through a special fitting.
If you smell gasoline in the closed garage where your vehicle is stored, walk along the entire fuel line, inspecting for leaks.

Note. A clogged filter is indicated by a prolonged noise from the fuel pump, heard after turning on the ignition. The unit cannot raise the pressure in the line to normal and does not turn off for a long time.

More serious problems are more difficult to detect. Both gasoline and diesel engine may suffer from improper operation or failure of injectors. Their functionality is checked by removing and connecting to a power source. The atomizer must create an even, beautiful “torch”; otherwise, it must be replaced.

The reason for the lack of fuel in diesel engine often becomes fuel pump, creating in the system high pressure. When the parts of the unit are worn out, the pressure in the line drops below normal, and little diesel fuel is injected into the cylinders.

Together with fuel filters It wouldn't hurt to check the air too. Blow out the contaminated element if you cannot replace it immediately.

Ignition faults

In cases where, when you press the gas pedal, you hear a shooting in the exhaust pipe or the engine begins to “triple” at idle speed, try to find a problem with the ignition system. Weak sparking at the electrodes of the spark plugs leads to incomplete combustion of the air-fuel mixture and loss of power by the power unit. The reasons for the system to malfunction look like this:

Problems with one or more high voltage coils.
The insulation of the high voltage wires running from the coils to the spark plugs has become leaky.
Due to the long service life, the spark plugs themselves have worn out.

The insidiousness of worn-out spark plugs is that during testing they give a normal spark. But there is high pressure in the engine cylinders, at which old spark plugs die out. This is why the engine does not develop speed, but sharp pressing the accelerator pedal causes “failure”. Spark plugs must be checked on a special stand that creates a pressure of at least 20 bar.

Diagnose breakdown high voltage wire Or you can insulate the candle in a dark garage. Open the hood, start the engine and watch it work. If you notice flashes of sparks on the “cradles,” install new parts.

A failure of the coil or a break in the high voltage wire is indicated by the complete failure of one of the cylinders. It's easy to test the wire: swap it with the neighboring one and make sure that the other cylinder has stopped working. This technique will not work with coils; special equipment is needed for diagnostics.

Motor problems

Critical wear of the cylinder-piston group of the power unit also leads to a decrease in power. There are other reasons why the engine revs poorly:

valve burnout in one or more cylinders;
lack of compression or its drop below the permissible level;
incorrect adjustment of thermal clearances between valve stems and rocker arms;
belt or chain drive gas distribution mechanism.

Most of the listed malfunctions are detected by measuring compression. A burnt valve does not completely seat in its seat, which is why the pressure in this cylinder drops to 2-3 bar, and sometimes to zero. A general decrease in compression in all cylinders to 9 bar or less indicates that they are “playing up” piston rings.

Advice. Before announcing the verdict on the cylinder-piston group, it is worth checking the thermal clearances with a feeler gauge. If some “specialist” recently made an incorrect adjustment and tightened the valves, then the compression will also decrease.

Similar errors occur when replacing a timing chain or belt, when the marks shift by 1 tooth. Consequences - violation of valve timing and loss of power plus unstable work engine. A similar effect is encountered by careless drivers who do not take care of their own car: due to wear, the chain (belt) stretches greatly and jumps on the gear camshaft for 1 tooth.

Too high oil consumption, penetrating into the combustion chambers through valve seals, also worsens the operating conditions of the power unit. From the inside, the chamber walls and spark plug electrodes become covered with soot, and the piston rings become coked and stuck. A sure sign of a malfunction is clubs blue smoke from the exhaust pipe.

Causes

There may be several reasons for the lack of proper speed gain:

There are problems with the air supply;
The ignition has failed;
Fuel system malfunctions have occurred;
There were problems with the exhaust system.

Fuel system problems are common for gasoline engines. They are the most common. Therefore, you should start with checking it.

Fuel system

If problems arise when accelerating the car, start checking by inspecting the fuel system.

Most often, the engine stops gaining momentum because the fuel pump fails. At first, this may have a slight effect, sometimes unnoticed. Over time, as the pump wears out, the speed and power will begin to drop, and the acceleration dynamics will decrease.
If the fuel pump is partially damaged, it still partially performs its functions, but is no longer capable of delivering the same volumes of fuel. This results in fuel starvation and power loss.
The best solution to a problem with the pump is to replace it. It is better to trust repairs to specialists.

Ignition

If the ignition fails, you will have to carry out due diligence all system components that may cause a drop in engine power and speed.

What to check	Peculiarities
Checking timing marks	If the marks are installed incorrectly, fuel will not be injected in a timely manner, and the correct frequency of spark supply will be disrupted.
	You will have to check all the sensors that take part in the operation of the ignition system. Special attention Pay attention to the crankshaft and camshaft position sensors. A regular test allows you to quickly determine whether the sensors are really to blame
Timing belt	If the belt has been in use on your vehicle for a long time, it may be at the end of its service life. Or it was installed incorrectly when replacing it. After all, it is enough to make a mistake by one tooth, and the performance of the car will be impaired, the car will not be able to accelerate properly
Spark plug	In some cases, they do not allow the car to start at all if there is a malfunction, but sometimes they lead to a noticeable drop in power. Remove them, check their condition, clean them, measure the distance between the electrodes. If they fail, simply replace them with new ones.

To finally verify the presence or absence of problems in the ignition system, it is recommended to conduct more detailed diagnostics.

Diagnostics

We suggest you familiarize yourself with several steps aimed at diagnosing the condition of the ignition system. This may help determine why the engine is not revving up.

Make sure that the electronic control unit is performing its functions. First of all, turn on the ignition and listen to whether the fuel pump starts working.
Measure the pressure in the fuel line. If the readings fall within 2.5-3.0 kg/cm3, then everything is fine.
If the measurement readings are normal, check the BitStop parameter using scan tools while cranking the crankshaft. If the parameter is indicated “no”, then the ECU receives the command to create a spark at the plugs and works well.
Using a high-voltage spark gap, you can check for the presence of a spark. After all, it’s not uncommon for worn-out, dirty spark plugs to be to blame.

Air supply

It is not uncommon for engine thrust to deteriorate due to a disruption in the normal air supply to create the air-fuel mixture.

If there is more air, the mixture will be lean because the amount of oxygen will exceed the amount of fuel. Hence the drop in power and decrease in traction.

The easiest way to solve an air supply problem is to replace the air filter. In order to prevent and prevent problems from occurring, this element should be changed twice a year.

If the engine speed increases, but the speed does not increase, there are several possible explanations for this phenomenon:

The pressure in the fuel system is too low;
The operation of the mass air flow sensor is disrupted. The sensor most often returns to its previous performance after cleaning. If it doesn't help, replace it;
The air filter is clogged. It is better to replace it;
The nozzle is clogged. This is mainly due to the low quality of the fuel you fill your car with.

Material on topic:

Exhaust system

Much less often, a drop in power and speed can be caused by problems with the exhaust system.

To make sure of this, check the condition of the catalyst for contamination or blockages.

It is the pollution that clogs the catalyst, which is why, despite all the possibilities, the car cannot squeeze out all the available power.

This is not to say that the VAZ 2110 has a very capricious engine. Although this largely depends on what kind of power unit is located under the hood of your “ten”. The first versions were not particularly reliable, but over time the engineers managed to make some progress.

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