Doesn't gain momentum. Why is the engine not picking up speed? Possible causes and solutions

The most unpleasant type of malfunction 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 pick up 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 complete list reasons causing inadequate behavior of the power unit.

Fuel system problems

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

1. 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 to work on Idling without load.
2. A common cause is a fuel pump mesh clogged with dirt located in the tank. Often, motorists ignore its replacement, installing only a new filter. To check the coarse mesh, you will have to disassemble the gas tank and pull out the pump.
3. 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.
4. If you smell gasoline in the closed garage where the car 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, audible after the ignition is turned on. The unit cannot raise the pressure in the line to normal and does not turn off for a long time.

More serious problems are harder to detect. Both gasoline and diesel engines can suffer from injector malfunction or failure. Their performance 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 a diesel engine is often the fuel pump, which creates high pressure in the system. 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.

Along with the fuel filters, it does not hurt to check the air one. Blow out the contaminated element if you cannot immediately change it.

Ignition faults

In cases where, when you press the gas pedal, a lumbago is heard in exhaust pipe or the engine starts to “trot” on idling, try to find a problem with the ignition system. Weak sparking on the electrodes of the candles leads to incomplete combustion of the air-fuel mixture and loss of power by the power unit. The reasons for the malfunction of the system look like this:

1. Problems with one or more high voltage coils.
2. Loose wire insulation high voltage going from the coils to the candles.
3. Due to the long service life, the candles themselves have worn out.

The insidiousness of worn candles lies in the fact that during the test they give a normal spark.. But in the engine cylinders there is a high pressure at which the old candles die out. That is why the engine does not develop speed, and sharp pressing of the accelerator pedal causes a "failure". It is necessary to check the candles on a special stand that creates a pressure of at least 20 bar.

You can diagnose a breakdown of a high-voltage wire or candle insulation 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.

The failure of the coil or the breakage of the high voltage wire is indicated by the complete failure of one of the cylinders. Testing a wire is easy: swap it with an adjacent one and make sure that the other cylinder has stopped working. With coils, this technique will not work; 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 is not gaining momentum:

• valve burnout in one or more cylinders;
• lack of compression or its fall below an acceptable level;
• incorrect adjustment of thermal gaps between valve stems and rocker arms;
• malfunctions of the belt or chain drive of the gas distribution mechanism.

Most of these faults are detected by measuring compression. A burnt valve does not fully fit into the seat, due to which the pressure in this cylinder drops to 2–3 bar, and sometimes even to zero. The general decrease in compression in all cylinders to the level of 9 bar or less indicates that the piston rings have run up.

Advice. Before announcing the verdict of the cylinder-piston group, it is worth checking thermal gaps probe. If recently some "specialist" made an incorrect adjustment and clamped the valves, then the compression will also decrease.

Similar errors occur when replacing a chain or timing belt, when the marks are shifted by 1 tooth. The consequences are a violation of the valve timing and loss of power plus unstable engine operation. A similar effect is faced by negligent drivers who do not monitor their own car: the chain (belt) is greatly stretched due to wear and jumps on the gear camshaft for 1 tooth.

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

Other problems

A modern car is equipped with an electronic control system for the power unit and flue gas neutralization. Since the technical condition of these systems directly affects the operation of the engine, power loss can occur for the following reasons:

• destruction and complete obstruction catalytic converter installed in the exhaust tract of a gasoline engine;
• a clogged diesel particulate filter has the same consequences - exhaust gases have nowhere to go and power unit"suffocating";
• failure of one or more sensors associated with electronic unit management.

Checking the patency of the converter and particulate filter it is simple: unwind the front flange of the device, opening the way for exhaust gases, and start the engine. If its performance improves significantly, change the catalyst to a new one or.

When the lambda probe fails, the engine does not pick up speed at the command of the controller. Without "seeing" the amount of oxygen at the outlet, the electronic unit cannot properly prepare the air-fuel mixture, therefore it goes into emergency mode. The mixing of fuel with air occurs according to the established indicators, which reduces the power of the motor.

The transition to the emergency operation mode is accompanied by the inclusion of the display check engine on the dashboard. A malfunction occurs whenever one of the main sensors fails - DMRV (in new cars - DBP), lambda probe or throttle position sensor. To check the performance of these devices, it is better to contact a competent auto electrician or a service station.

One of the signs of an engine problem is usually that the engine does not pick up speed ("does not spin up", as many motorists say). There can be a lot of reasons that the engine is not gaining momentum, an accurate diagnosis can only be made by an experienced diagnostician, but an initial check can be carried out on your own. So, what are the reasons for the engine not picking up speed?

The engine does not pick up speed. What to check first?

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

For diesel engines, the test begins with equipment with injectors, because it is this that most often causes engine power loss. In addition, the possibility of air leakage in the fuel system should be excluded.

As well as gasoline, and diesel engine worth it because it could clog and affect engine thrust.

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

In addition, you should carefully inspect the wires and candles to make sure they are intact and in good condition. Engine thrust can also be affected by a failed sensor (DMRV, DHX, crankshaft sensor, camshaft sensor, throttle position sensor, etc.).

Air supply. Another common reason why the engine does not pick up speed is air leaks on the way of the fuel-air mixture into the cylinders. Also, it should.

Exhaust system. Many cars have a noticeable effect on traction, so check exhaust system it is worth starting with the catalyst (if any).

Another very common reason for an engine not revving is bad fuel. If you refueled at an unknown gas station, the problem may be 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.

During the operation of a diesel or gasoline power unit, a motorist may encounter a situation where, when the gas is pressed, the engine does not pick up speed. It is worth noting that after installing HBO on a car, such a problem often appears when the engine does not gain momentum on gas, although it drives normally on gasoline. Malfunctions of various kinds may lie in simple things, but may indicate the need for serious engine repairs. More on this later in the article.

If the internal combustion engine has stopped gaining momentum, first of all, you need to analyze how and when it manifested itself. That is, the engine refused to spin up unexpectedly, or the problem with the development of revolutions progressed gradually. It is also necessary to pay attention to the absence or presence of other symptoms.

The bottom line is that if a previously good engine refuses to pick up speed after performing any repairs or other operations, this may be the result of errors during assembly, a sensor not connected, and so on. In such cases, the breakdown can be more accurately and quickly determined using an independent inspection or the immediate return of the car to the service where the vehicle was repaired before.

If the engine does not gain momentum for no apparent reason, troit, the car systematically stalls, and so on, then the motor requires in-depth diagnostics. The causes of such a malfunction can be conditionally divided into complex and simple, appearing immediately or having received prerequisites.

Why does the engine rev slowly?

The set of revolutions while driving is strongly affected by the composition, efficiency of supply, completeness of combustion and the timeliness of ignition of the air-fuel mixture. A common reason that the internal combustion engine does not gain momentum (diesel, carburetor, injector, gas car) are malfunctions in the fuel and air supply systems, as well as in the ignition system.

Why does the engine rev and stall?

It often happens that the internal combustion engine is gaining momentum and stalls as a result of a clogged fuel pump filter mesh. The fact is that deposits from the gas tank accumulate on this filter over time. Due to the pressure in the system, there is not enough fuel, the pump performance decreases, and the engine itself cannot function normally in various modes. To fix the problem, you need to clean or replace the mesh. However, this is only one possible reason among many others, which we will consider below.

Simple reasons due to which the engine is not gaining momentum, how to eliminate them

Experts highlight the following:

Most of the above reasons, the car owner can determine and eliminate on their own. It is necessary to check the wires of the ignition system and spark plugs, measure the pressure in the fuel rail (on injection engines), inspect the air filter for contamination, replace the fuel filter, and so on.

Complex, sudden reasons why the engine does not gain momentum, how to eliminate them

Now let's look at problems that may require some skills, knowledge, diagnostic equipment, or be a reason for a trip to a car service. In this list of malfunctions, as a rule, there are those when the engine does not gain momentum due to the failure of one of the ECM elements, the power supply system, ignition, and so on. That is, here we are no longer talking about “consumables” (pipes, filters, wires, candles), but about details. At the same time, consider whether the malfunction progressed gradually or the breakdown occurred unexpectedly.

• One of the reasons is the downed timing phases. Violation of the synchronous operation of the gas distribution mechanism with respect to the exhaust and intake strokes entails the untimely opening of the intake and exhaust valves. The malfunction appears due to errors when replacing the timing belt, if the belt jumped one or more teeth. Another reason may be incorrectly adjusted valves (the problem does not manifest itself sharply), malfunctions of the timing chain drive, various breakdowns in the variable valve timing system, and so on.
  
  
• Unexpected breakdowns include the failure of the ignition module, as well as malfunctions of the ignition coils. In this situation, misfires begin, the engine troit and can no longer gain momentum normally.
  
  
• Also check nutrition injector nozzles. If there are problems with the wiring, the control signal to the nozzle comes intermittently or not at all. As a result, the nozzle does not open in a timely manner, misfires appear in one or more cylinders, the engine loses power and does not gain the required speed.
  
  
• The fuel pump or injection pump on a diesel engine may fail. As a rule, this malfunction does not appear immediately (with the exception of damage to the electrical wiring to the pump). More often, pump performance decreases gradually. But sooner or later, the fuel pump will begin to pump fuel very weakly, the pressure will only be enough to work on the twentieth. An increase in speed and load will lead to the fact that the motor does not spin up, stalls under load, and so on.
  
  
• Sometimes similar symptoms entail severe contamination of the injector. Driving on low-quality fuel, as well as ignoring the required injector cleaning procedure every 40 thousand km. mileage may indicate that the performance of one or more injectors has dropped significantly.

  Ultrasonic nozzle cleaning

• The engine speed can also be affected by the state of the EGR system, as well as the throughput of the particulate filter or catalyst. As a result of a clogged catalyst, exhaust gas removal deteriorates, the engine literally “suffocates” and does not gain normal speed.
  
  
• In parallel, you need to check different ECM sensors (DMRV, TPS and others). Their incorrect functioning can affect the composition of the mixture (the amount of air and fuel supplied to the engine).

Untimely maintenance of the engine, which leads to an irresponsible attitude towards the car

Finally, I would like to say that the timely replacement of wires and spark plugs, filter elements and fuel pump filters, cleaning of the injector, throttle valve, correct throttle adjustment and other service procedures will give you the opportunity to get the maximum power from your engine. Untimely maintenance of the internal combustion engine, on the contrary, can lead to destabilization of the engine and other more serious problems up to the overhaul.

As for cars with HBO, the correct setting and installation, timely replacement of filters, as well as maintenance of other HBO elements will depend on both the engine power and its speed, and the overall service life of the internal combustion engine.

During the operation of their car, many drivers begin to notice that the engine is not gaining momentum properly. Accordingly, the dynamics falls, the possibilities of maneuvering and overtaking are reduced. It is impossible to put up with such a problem.

Causes

There can be several reasons for the lack of a proper set of revolutions:

• There were problems with the air supply;
• The ignition has failed;
• Malfunctions have occurred fuel system;
• There were problems with the exhaust system.

Fuel system problems are common for gasoline engines. They are the most common. Therefore, it is necessary to start with its verification.

Fuel system

If there are problems during acceleration of the car, start the check with an inspection of the fuel system.

1. Most often, the engine stops gaining momentum, because the fuel pump fails. At first, this may affect slightly, sometimes imperceptibly. Over time, as the pump wears out, speed and power will begin to fall, acceleration dynamics will decrease.
2. With a partial breakdown of the fuel pump, it still partially performs its functions, but it is no longer able to supply the previous volumes of fuel. Hence there is fuel starvation, power drops.
3. The best way to solve the problem with the pump is to replace it. Repairs are best left to professionals.

Ignition

If the ignition fails, here you will have to carry out a comprehensive check of all the components of the system, which can cause a drop in power and engine speed.

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

Diagnostics

We suggest that you familiarize yourself with several steps aimed at diagnosing the condition of the ignition system. This can help determine why the engine is not gaining momentum.

1. Make sure that the electronic control unit performs its functions. First of all, turn on the ignition and listen to see if the fuel pump turns on.
2. Measure the pressure in the fuel line. If the readings fit into 2.5-3.0 kg / cm3, then everything is fine.
3. If the readings are normal, check the BitStop parameter using scan tools while cranking. If the "no" parameter is indicated, then the ECU receives a command to create a spark on the candles and works well.
4. Using a high-voltage arrester, you can check for a spark. After all, it is not uncommon that worn, contaminated candles are to blame.

Air supply

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

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

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

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

• Too little pressure in the fuel system;
• The work of the DMRV is disrupted. The sensor most often returns to its previous performance after cleaning. If it doesn't help, replace;
• clogged up air filter. It is better to replace it;
• Nozzle stuck. This is mainly due to the low quality of the fuel you fill your car with.

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Exhaust system

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

To verify this, check the condition of the catalyst for the absence of contaminants, blockages.

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

It cannot be said 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 reliable, but over time, engineers managed to make some progress.

Many motorists have encountered the problem of unstable engine operation: it does not gain momentum, does not develop sufficient traction, and sneezes. It is urgent to look for a malfunction problem, otherwise the motor may simply “die”.

Possible malfunctions

Why is the engine not picking up speed? The causes of unstable engine operation may include problems in various vehicle systems and (ICE).

Among possible faults in electrical circuit systems and electronic sensors, reading the parameters of the internal combustion engine, the state of the gas distribution system (valves, camshaft drive mechanisms), the serviceability of the crank mechanism and, the fuel supply and purification systems, the intake and exhaust systems play a role.

Interesting to know! If the electronic control unit of the ignition system has failed on the road, you can get to the nearest service station using the Hall sensor, which is located next to the electronic control unit.

Electrical part

Pay attention to the distributor, ignition coil and high voltage wires. Make measurements on the wires (for their breakage) using an ohmmeter or a test light. If there is no light bulb, look for a broken wire.

Ballast resistance can also cause an engine to rev poorly. The ribbed block under the windshield is the ballast resistance. Having found a malfunction in the ballast resistance, you must immediately replace it, since it cannot be repaired (you can, of course, try to repair it in a specialized workshop).

Check the distributor housing for mechanical damage and chips, carbon contacts of the central electrode. Check the resistance of the tips of the candles with an ohmmeter. If the problem persists, try adjusting the ignition timing. After setting the distributor to the neutral position, slowly turn it to the left / right - the operation of the engine will change.

One of the reasons why the engine does not develop speed is the fuel system. In the fuel supply system for gasoline engines, a gasoline pump plays one of the main roles. You should also check the fuel filter (if necessary, replace it). The filter may not pass fuel due to the presence of water or mechanical impurities in it.

Work diesel engine depends on the operation of the fuel equipment and injectors. The failure of the injector nozzles or plunger pairs of the fuel pump affect the engine power, up to the point that the engine does not start at all.

Also make sure there are no fuel leaks in the fuel system. When leaking fuel, look for the cause in leaks. Fuel filter diesel engine in the summer may not pass diesel fuel due to water that has accumulated in the filter, and in winter, due to the use of low-quality winter fuel, there may be paraffin deposits on it, therefore it should be changed.

Electronic engine management system

Modern engines to ensure low fuel consumption and high vehicle acceleration dynamics, they have many electronic systems, which determine the position, detonation of the fuel in the combustion chamber, the position of the throttle and air dampers depending on the temperature of the engine and the external temperature, on the mode in which the engine is running (acceleration or coasting - forced idling system).

The state of these systems affects the quality of the engine, its efficiency. The sensors of these systems are located in various places on the engine and engine compartment, and the operation of the car depends on their quality work.

Other reasons

Causes not directly related to the state of engine control and adjustment systems may include problems with air supply systems, exhaust gases, fuel quality.

The condition of the intake system is affected by the conditions in which the car is operated. When driving in dusty areas, the air filters should be replaced more frequently than recommended by the manufacturer.

When the filter is clogged, lean occurs combustible mixture in the combustion chambers of the engine. There is incomplete combustion of fuel, or, as they say, the engine overflows. Soot forms on the candles, the traction characteristics of the engine deteriorate.

If during operation the fastening of the elements of the intake system is loosened, air is “sucked in”, the exhaust gas recirculation systems do not work properly, the fuel mixture due to excess air, the engine does not develop full power. In this situation, it is necessary to check the condition of the fastening of the intake manifold and carburetor.

Exhaust system

Attention! If the car has a catalyst, then start checking the exhaust system with it. Check the condition of the lambda probe, the condition of the catalyst, whether it is “clogged” (due to the poor quality of the fuel, carbon deposits may form on it). With a faulty catalyst, exhaust gases will not completely exit the cylinders, which will lead to poor filling of the combustion chambers with an air-fuel mixture and a decrease in engine power.

In the event of a leak in the seal between the exhaust manifold and the cylinder block, exhaust gases will burst into engine compartment, which can lead to engine overheating, incorrect operation of electronic systems. This problem can be fixed by tightening the manifold or replacing the gaskets under the intake manifold.

High-quality fuel is the key to the health of your car. But none of us is insured that at some gas station we will not be slipped low-quality fuel. Sometimes, with bad fuel, the engine not only junk, but generally refuses to start. In this case, you will have to drain all the fuel and rinse the tank. Engine plugs will tell you about bad fuel: if there is a red coating on the contacts of the candle and the “skirt” of the central electrode, then the fuel is good. Black soot on a candle indicates poor quality fuel with a high content of impurities. The presence of soot degrades the quality of the candle.