lawn mower does not develop momentum cause

Piston group wear

does, develop, momentum, cause

With prolonged operation of the engine, the piston group naturally wear out, 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 engine operation, the use of poor quality fuel and oil.

Violation of the gas distribution mechanism

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

Fuel quality

The use of high-quality gasoline or diesel fuel is a guarantee of a long-term engine life and obtaining maximum power indicators from it. But none of the drivers is completely insured against refueling with low-quality fuel, the use of which threatens not only a significant decrease in power indicators, but also the inability to start the engine. Regular use of low-quality gasoline manifests itself in the intensive formation of carbon deposits on the cylinders, pistons, catalyst and in the exhaust manifold, as well as in increased wear of the cylinder-piston group.

Ignition system malfunctions

Most often, in the ignition system, malfunctions that reduce engine power relate to spark plugs, in which the gaps between the electrodes can be violated, carbon deposits have been deposited on them, or the insulator is damaged. Deterioration of spark quality or its absence is often the result of breakage, contact failure or integrity of high-voltage wires, ignition coil and distributor.

The main reasons for the lack of engine dynamics

A driver who constantly operates a car easily detects a deterioration in the dynamic characteristics of the engine, which manifests itself in sluggish acceleration, poor traction, increased fuel and oil consumption. These processes are often accompanied by the appearance of a 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 air supply problems.
  • Malfunctions of the gas distribution mechanism.
  • Fuel supply system malfunctions.
  • Sensor malfunction.
  • Ignition system malfunctions.
  • Weak compression in the cylinders.
  • Incorrect operation of the vehicle ECU.
  • Specific malfunctions of engines with a turbocharger or carburetor.

Sensor malfunctions

In modern engines, in order to achieve a combination of high dynamics and low fuel consumption, readings of various sensors are used that determine the position of the crankshaft, air flow, detonation in the combustion chamber, the composition of exhaust gases, the position of the air and throttle valves, and external temperature. The data from them goes to the engine ECU, and affects the mode of its operation. A malfunction of one or another sensor makes the operation of the power unit not optimal, which manifests itself in a loss of power.

ECU malfunctions

All processes of a modern car are controlled by an electronic unit that collects sensor readings and, on the basis of the program incorporated into it, regulates the operation of the engine. The operation of the ECU can be changed by adjusting different modes of operation depending on the required consumption and type of fuel used, vehicle operating conditions and other characteristics. Malfunctions in the electronic unit or its incorrect setting can lead to both a loss of power and the inability to operate the engine itself.

10 reasons why the engine is not picking up speed

When operating a car with a gasoline or diesel engine, sometimes a situation arises when the expected increase in revolutions does not occur when the accelerator pedal is depressed. A serviceable power unit should instantly respond to an increase in the combustible mixture in the combustion chambers with an increase in the crankshaft speed, but if this does not happen, you need to look for a malfunction. It can be caused by both fairly simple and easily fixed things, and serious breakdowns.

The engine gains speed poorly or does not pull at all?

Why is the engine not picking up the speed it needs to run correctly? Many drivers ask themselves this question. During the operation of engines of various types, they often encounter a situation when, when you press the gas pedal, the engine does not react in any way and does not gain the required speed.

Often, such problems are encountered with vehicles equipped with LPG, although when switching to gasoline, the problem disappears. Malfunctions of a different plan can entail both rather serious repairs and simple preventive measures. Let’s take a closer look at why the engine picks up speed poorly, both on gasoline and diesel fuel.

In the first case, it is very important to try to analyze under what conditions this happened and how it manifests itself. Be sure to try to identify all the accompanying symptoms.

The failure of a fully functional internal combustion engine to gain the required speed after service work or repair is usually the result of improper assembly, connection errors, etc. such situations allow you to instantly identify malfunctions by inspecting or returning a car to a repair station.

Possible reasons why the engine does not develop speed are divided conditionally into categories. First, let’s deal with simpler, one might say insignificant malfunctions. The set of necessary indicators when driving is very dependent on the completeness of combustion, the composition of the mixture, the efficiency of supplying it in the right volume and timely ignition.

One of the most common reasons why the speed cannot reach the desired value is the disrupted operation of the ignition systems, fuel and air supply:

  • Significantly contaminated air filters reduce the possibility of air ingress through the filters. In such a situation, the engine starts to work unevenly, loses power, as a result of which it will not be able to pick up speed. One of the most common reasons is the appearance of branches, dirt, bags, etc in the air filter;
  • You need to pay attention to the suction for the intake of excess air. The problem may arise unexpectedly or as a result of gradual progress. Working on a strong suction, it is very difficult for the motor to gain momentum. The proportions of fuel and air in the fuel-air mixture deviate significantly from the normal value. As a result, the mixture turns out to be very lean in gasoline and rich in air. An engine with such a mixture will start without problems, but will not work without interruption and will not be able to gain speed with the slightest movement;
  • The unit is not receiving enough fuel. Usually, a filter acts as the culprit, which can easily become clogged with foreign objects. Usually, there are no problems with starting the internal combustion engine, since the fuel level is normal, but the car jerks, does not respond in a timely manner to manipulations with the gas pedal. The revolutions may not reach the level of a certain mark of the tachometer;
  • A dirty filter mesh on the gasoline pump, since over time the formation of plaque from the tank on it is a natural process. The lack of the required pressure in the system leads to a drop in pump performance. Normal operation of the motor is impossible in different modes: the engine will pick up, speed is needed and immediately stall due to clogging of the mesh;
  • Disrupted work of wires and candles makes the ignition of the combustible mixture problematic. The process of igniting the fuel charge is untimely, the power drops, and accordingly the revolutions will not increase. The reason for these manifestations is usually contamination and oiling of the candles, damage to its body, gaps when mounting on the electrodes;
  • Engine tripping in case of breaks in high-voltage wires, misfiring, impaired dynamics of the engine speed set.

Serious malfunction requiring a certain level of skill, knowledge and special equipment or contacting a workshop. It’s no longer about consumables, but about the details:

  • Perhaps the most important reason is the disrupted phases of the timing. The balanced operation of the gas distribution mechanism is disrupted due to untimely opening of the valves. Such troubles usually appear after unsuccessful attempts to replace the timing belt, especially when jumping teeth. Also, the reasons include valves that are incorrectly adjusted, malfunctions in the valve timing and even a breakdown of the timing drive;
  • Disrupted operation of the ignition module and coils. Ignition misfires are becoming commonplace, and the engine simply cannot reach the rpm required for normal operation;
  • It is worth paying special attention to the power supply of the injectors on the injector. The control signal does not act on the injector, or it happens intermittently due to improper wiring;
  • Violations in the operation of the gasoline pump, and if the diesel engine, then the injection pump. The problem develops gradually, it all starts due to a gradual weakening of the ability to pump fuel, and as a result. a lack of pressure. As a result, with a high load of the engine, it will start to stall more and more often;
  • The problem of contamination of the injector occurs when the units operate with extremely poor quality fuel. Be sure to clean the nozzles for at least 30 thousand;
  • Incorrect operation of the sensors of the electrical system can even affect the composition of the combustible mixture.

What is the bottom line?

Considering all the problems with the fact that the internal combustion engine is slowly gaining momentum, it would be advisable to carry out a diagnostic check for errors as soon as possible. As a matter of urgency, such a procedure must be carried out, in the case when “check” lights up on the tidy.

There are rarely cases when the engine does not develop speed due to the failure of the ECU. Such troubles can arise due to engine washing and negligent diagnostic maintenance of the firmware.

The result of such an intervention is an inadequate perception of the ECU speed: low are taken for high, and vice versa. The maximum power of the internal combustion engine can be obtained subject to the timely implementation of all routine maintenance provided by the manufacturer and other equally important service activities.

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The scooter is not gaining momentum: causes, diagnostics, troubleshooting

Engine lacks power

Start the engine and turn the throttle up a little for observation.

If the speed does not increase as it should, then it may be

clogged air filter;
clogged gas filter;
clogged muffler;
clogged carburetor;
faulty starter concentrator;
clogged or leaking rubber benzo and air pipes leading to the gas valve and carburetor.

Unscrew the candle,

check the color of the candle

Candle color is “wrong”

faulty or dirty candle;
re-enriched mixture;
inappropriate glow number of the candle;
piston problems. splashes with oil.

If there is no spark or it is weak

faulty or dirty candle;
broken or “shorted” wiring;
torn or “shorted” ignition coil;
interrupted or “shorted” inductive ignition sensor;
faulty ignition lock;
faulty generator.

Check if the engine is overheating.

If yes, then it could be

too lean mixture;
poor quality gasoline;
strong carbon deposits in the combustion chamber;
early ignition time.

Check the compression in the cylinder.

If there is no compression or low (4-6 atm)

How Does A Lawn Mower Work? — Lawn Equipment Repair Tips

faulty petal valve. for 2t engines;
leakage through the crankcase, for example through the crankshaft oil seals. for 2t engines;
burnt or loose valves. for 4t engines;
torn cylinder head gasket;
burnt out or worn out piston and / or cylinder and / or rings;
crack in the cylinder head.

Check ignition timing.

If the ignition timing is Wrong

faulty switch (CDI);
faulty generator;
generator rotor installed incorrectly.

Accelerate quickly or continue driving at high speed.

If the engine knocks (detonates)

too lean mixture;
strong carbon deposits in the combustion chamber;
poor quality gasoline;
clutch slips.

the scooter does not gain momentum and does not travel more than 40

the moped does not travel more than 40, what to do:

Often many people ask what to do, the moped does not travel more than 40 and does not gain momentum from the spot. It’s simple if your Honda dio is not gaining momentum.

1) We change the candle to a new one, because it can be broken, changed it, tried it, did it work? Yes it’s good! No. bad, let’s move on! I also advise you to clean the cylinder head and piston from carbon deposits with sandpaper “0” (because of this, sometimes it pulls badly).

2) We clean the air filter.
How to properly clean the air filter. someone blows it in the hope that everything is fine, I will say right away you are mistaken! The filter should be washed but not in water or soap! And in pure gasoline, after the washing procedure, grease the filter with oil and let it soak! Everything can be put!

3) Adjust the carburetor. read how to adjust the carburetor here.

4) Perhaps the muffler is clogged and needs to be cleaned. how to clean the muffler, read this article. (because of a clogged muffler, there are a lot of problems, mainly after cleaning the moped, it becomes unrecognizable!)

5) If it does not pull, then you need to change the variator belt and it is advisable to replace the variator rollers (we read about all this here, the rollers and the belt also affect the maximum speed)

6) Check the piston, it may be time to change the rings or replace the piston if necessary.

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The scooter does not pick up maximum speed. the main reasons

If the scooter, immediately after the purchase, easily squeezed out its intended 60 kilometers per hour (we are talking about fifty kopecks), and over time began to gradually slow down at the maximum speed, you should not panic. Sometimes it is enough to determine the reason for this behavior of the scooter and return everything to its place within a few minutes.

It should be noted that some Chinese pseudo-fifty dollars, while new, easily accelerate to 70 km / h or more. Pseudo, because usually there are not 49.9 cubes at all, but from 62 to 82cc. This is a deliberate step by Chinese engineers. Putting a larger piston does not entail any cash costs, but it significantly affects both dynamics and maximum speed. Such scooters are not supplied to Europe, since there is strict control over both quality and compliance with all major environmental and cubature standards.

But in the countries of the post-Soviet space, they are in great demand, due to their low price, large size and pleasant appearance (not always).

Chinese cubature scooters also have sufficient demand to be affected by the reason for the decline in maximum speed. Sometimes it happens that a Chinese scooter with an engine capacity of 150 cubic centimeters cannot accelerate more than 60-70 km / h. These are unacceptable indicators, which must be understood and corrected, which we will do next.

So, the main reasons that entail a decrease in maximum speed, and sometimes dynamics:

1) The variator belt has worn out by more than 1-1.5 mm, after which it cannot reach the maximum variator radius, and therefore there can be no talk of the maximum speed.

To understand this, take a look at the picture below.

The left cheek indicates the variator itself, the right cheek the clutch. The side shows the location of the belt and rollers during all operating ranges of the scooter.

We are interested in top gear, in which the variator belt should be as close to the edge of the cheeks as possible.

If its width is below the permissible norms, it cannot do this, hence the maximum speed drops, sometimes up to 15 km per hour less than the norm (with severe wear of the belt). Therefore, it is important to periodically check the belt width with vernier calipers, and if worn up to 1.5 mm (ideally 1 mm), replace it with a new one. You can find all factory sizes of scooter belts on our website.

2) The wear of the variator rollers on the scooter will also reduce the maximum speed. There are two factors here. a decrease in the weight of the roller itself and a change in shape from round to square (triangular, it does not matter), when the roller does not roll out in the ditch, but simply slides in it.

Here are photos of the worn out rollers, which should not be allowed:

Further comparison with the new videos:

To avoid such situations, check the rollers for wear every 3-4 thousand km. Someone will say that they should last much longer, but this only applies to high-quality and branded spare parts made of durable material. They cost 5-6 times more expensive than ordinary Chinese ones, and they pass about as many times more. In my opinion, it is better to change periodically cheap videos for 5 than to buy branded ones for 30. However, for serious tuning, it is still better to pay attention to the quality.

3) Piston wear on a scooter is one of the most important factors in which both maximum speed and dynamics are reduced. The engine simply loses power and cannot reach its original performance. At the same time, the compression reading plays a key role in determining piston wear. It can be measured with a conventional automobile compression gauge at any service station. If these indicators are less than 7 atm, the piston and rings on the scooter engine must be replaced. In this case, it is better to immediately clean the windows in the cylinder from carbon deposits, as well as the cylinder head from the inside. Remove the old gaskets under the cylinder and head and replace them with new ones. Take seriously the replacement of the CPG, install the rings and the direction of the locks correctly.

It is important to get a proper break-in and not to overheat the scooter engine. When the parts of the cylinder. piston group have not worn down well enough, any loads can lead to overheating.

4) A clogged air filter on the scooter will significantly reduce engine power as it lacks air. In this case, the mixture is enriched, there is no overheating. With constant driving on a rich mixture, the period of carbon formation in the engine decreases. In addition, fuel consumption increases, dynamics and top speed decrease. There is a black velvety coating on the electrodes of the candle.

5) A clogged muffler on a scooter (usually only on two-stroke scooters) greatly reduces engine performance, often a scooter cannot accelerate more than 30-40 kilometers per hour. This disgrace is treated by burning the muffler. I will not describe the whole process, we have already considered.

6) A dirty carburetor on a scooter on a scooter (of course, from the inside) cannot realize the correct supply of fuel to the combustion chamber, and will also prepare a mixture in the given proportions. In such conditions, reaching the maximum speed on a scooter is doubtful. To fix the problem, you need to remove the carburetor, then remove the float chamber cover, remove the float and shut-off needle. After that, you need to thoroughly rinse and blow out all the channels of the carburetor. You can use gasoline and a compressor, but not everyone can have such an expensive thing as a compressor at hand.

I use such a spray, I’m happy with the result:

You can find out more about how to properly clean the carburetor here.

8) Incorrectly adjusted scooter engine valves (only four-stroke scooter) can lead to engine overheating, reduced top speed, dynamics, poor idle performance. It is necessary to periodically check the valve clearance with a feeler gauge. Let me remind you that for the inlet it is 0.05 mm, for the outlet. 0.1 mm.

You can read detailed instructions on how to adjust the valves on a scooter here.

9) Any chokes and restrictions on the scooter prevent the engine from reaching maximum speed.

On Japanese and Chinese scooters with engine displacement up to 50cc, the limiters are usually installed in the commutator. The switch does not allow the engine to spin more than a certain speed (usually 6500-7000), and the engine, which quickly and rapidly accelerates to 55-60 km per hour, suddenly stops abruptly and completely refuses to go faster.

In terms of driver safety and engine durability, this is a huge plus. Increasing maximum engine speed always affects durability. In this case, the engine will last less, after which a major overhaul will be required. over, the service life is directly proportional to the maximum speed.

10) The gasoline with which you fill the scooter must only be of the brand specified by the scooter manufacturer.

11) Poor quality engine oil (in both two-stroke and four-stroke engines) may slightly reduce the maximum speed.

12) Wear of the crankshaft bearings on the scooter, the crankshaft itself, as well as the rest of the engine will also prevent it from spinning up to the required speed, therefore, the maximum speed will again not be reached.

13) Incorrectly adjusted carburetor on the scooter.

14) Large rider weight, riding with a passenger, driving against strong winds. all this can lower the maximum speed on the scooter, especially if the piston is already a little hooked. At the same time, under normal conditions, everything may be fine.

We examined the main malfunctions in which the scooter cannot reach those additional 10-15 km, which we sometimes lack. They can be present both singly and in a complex. I hope this article will help you in solving all these problems. If you have something to add or want to ask a question, share your experience or life story related to a scooter, write a comment and keep the conversation going. Good luck with the repair.

Reason 1. So-so fed

The quality of the fuel directly affects the behavior of the car. You can press the pedal into the floor as long and abruptly as you like, but you won’t get the effect. The car will sneeze, slow down and suffer with you. The simplest thing is to drain the gasoline and pour 5-10 liters from another gas station. If it was in him. the symptoms will disappear immediately. And if not in it. then fill back the old one. do not waste the good. We wrote about the consequences of filling low-quality fuel here.

Reason 5. We ignite the movement

The operation to check the ignition unit is recommended to be done in the service, however, if you are an electrician, you can independently inspect high-voltage wires. You don’t need special knowledge to revise the candles, so unscrew and see their condition. It will be easier if the manual for the car is preserved. the diagnostic procedure is detailed there.

Reason 4. Pressure is such pressure

Look at the manual and determine what pressure is typical for the car. Find a regulator on the line and see if it leaks. The second reason is misconfiguration. Excessive pressure is generated in the system, which affects the abnormal behavior of the vehicle. Equip yourself with an air pump for testing: raise the pressure level to the prescribed level and dump the fuel into the tank. Operations must be performed at the same time. If the fuel was dropped earlier, the regulator should be replaced.

If you have an injection engine, look for a fuel pump in the gas tank. With a carburetor engine, the pump is located directly on the engine, under the hood.

7 reasons why the car won’t drive when you press the gas pedal

“The car does not drive when you press the gas pedal!”. with these words frustrated drivers burst into the auto repair shop. “Well, okay,” says the bearded mechanic and orders to leave the “iron horse” outside the gate. “Let’s see and figure it out,” he draws out. lighting up. While the next master in our country thinks, we will explain the main reasons why the car does not want to accelerate when you press the gas.

Reason 2. Tired filter

The air filter tends to get dirty. After a critical point, it ceases to let air in sufficient quantities, which significantly complicates the operation of the motor. You can notice this problem by the increased fuel consumption or when checking the part. To make it happen. open the hood, remove the filter from the case. If the condition is unsatisfactory, change.

Reason 6. Pressure and air flow sensor

The car does not consume pure gasoline, but converts it into a fuel-air mixture. Its quality depends on how well the car will respond to pressing the gas pedal. If the sensors are broken, the calculations to create the optimal mixture will be erroneous, which means that the car will lose traction.

Do not assume that a sensor malfunction is displayed on the dashboard. If everything was easy, diagnosticians would not be useful. as specialists. The vehicle control system is programmed for a short circuit and a wire break. If the reason is different, then you need to look for the breakdown yourself.

Reason 3. Stubborn fuel cell

The fuel filter can also become dirty. He does not supply a sufficient amount of the mixture, the power of the car drops, it does not respond to pressing the gas pedal. Remove the filter and inspect for external damage. Then blow it out. If the blowing does not go at all or for its implementation it is necessary to blow out more than one pair of lungs. replace it. A serviceable element does not create obstacles for verification and is easily blown through.

Incorrect ignition timing

It often happens that unlucky car owners, wondering why the engine does not develop speed, forget about the ignition moment, although it is he who plays the most important role in the operation of the power unit. Timely ignition of the fuel mixture in the combustion chambers depends on it. If the ignition timing is set incorrectly, you will never, by any means and methods, achieve the coordinated operation of all engine systems and mechanisms.

In injection power units, the corresponding sensors are responsible for the correct moment. Their job is to collect information and transfer it to an electronic control unit, which in turn regulates the angle. There are no such sensors in carburetor engines, so the ignition is set manually by scrolling the top of the ignition distributor.

Setting the correct angle yourself and without special equipment is not easy, although possible. At service stations, a special stroboscope is used for this, with the help of which the specialist determines the position of the mark on the crankshaft at a certain position of the distributor.

Fuel level in the float chamber

The fuel level in the float chamber can also affect the operation of the power unit. If it is lower than it should be, the concentration of gasoline in the combustible mixture is reduced. Because of this, the engine does not develop power. At an overestimated level, the mixture, on the contrary, is too rich, but more than the norm enters the combustion chambers. Before entering the cylinders, it does not have time to warm up in the intake manifold, which leads to detonation and loss of speed.

The fuel level is regulated by bending (unbending) the float mounts.

Clogged air and fuel filters

Needless to say, the filters need to be changed every 7-10 thousand kilometers, and in special operating conditions, twice as often. Contamination of these elements causes difficulties in the supply of fuel or air to the manifold and leads to malfunction of the engine. The lack of normal fuel pressure in the fuel line causes the fuel mixture to become leaner, and in the event of problems with the air supply, it is re-enriched. In both the first and second cases, the engine “suffocates”, overheats, loses power, speed, consumes more fuel.

A similar malfunction is eliminated by replacing the filter elements.

Booster pump, carburetor channels and jets

Continuing the topic of the power loss of the carburetor engine, one cannot fail to mention the accelerator pump. It is on its serviceability that the response of the power unit to pressing the accelerator pedal depends. Most often, the problem lies in the fuel supply, and the “nozzles” of the sprayer, through which gasoline is fed in a thin stream, are to blame. To check the operation of the carburetor accelerator pump, you will need to remove the air filter to open a view of the first chamber. Next, you need to open the throttle and hold it for a few seconds. In this case, a thin (about 1 mm) stream of fuel should be pulled out of the “nose” of the accelerator, directed exactly into the second chamber. If the jet is weak or curved, this is a sign of a clogged spray nozzle, nozzles, and accelerator pump valves. This problem is solved by cleaning them.

Cold engine

It would be wrong to demand full power from the power unit until its temperature reaches the operating indicator (90 0 C), especially when it comes to a carburetor-injected engine. A cold engine does not fully rev, even with the choke fully closed. The fuel mixture must be warmed up before entering the combustion chambers. Otherwise, the car will “jerk” and the engine will stall and detonate. So, if your car is equipped with a carburetor engine, do not rush to leave until it warms up.

Sensor malfunction

Compared to a carbureted one, an injection engine benefits from the fact that its operation is electronically controlled, and if any problems arise, the driver will know about them by an error signal on the control panel. He will only have to connect the tester and read the code to determine which of the nodes has failed. This happens thanks to electronic sensors that control the operation of the main systems and mechanisms. But they are not eternal either.

Gaps between electrodes

The next reason why the engine is developing slowly or not developing at all, may be an incorrect gap between the electrodes of the spark plugs. I had a normal car with a normally working engine, but you didn’t like something, and you decided to change the candles, but did not read the manufacturer’s recommendations. An error in the gap of one tenth or one hundredth of a millimeter will certainly make negative adjustments to the operation of the engine. Depending on its increase or decrease, it may be difficult to start, loss of traction, decrease in power, excessive fuel consumption, etc.

When it comes to clearances, we cannot fail to mention two-stroke engines. For them, candles are one of the most important elements that ensure stable engine operation. So, if the two-stroke engine does not develop speed, the first step is to check the condition of the electrodes and the compliance of the gap with the recommended indicators.

Malfunction symptoms

It is not difficult to determine that the engine is not developing the speed that it should develop, especially if you have driven a car before and you know its native characteristics. Those drivers who have encountered a similar problem in their practice know that a decrease in power is characterized by sluggish acceleration, loss of dynamics, traction, as well as engine overheating and increased fuel consumption. Sometimes these processes are accompanied by gray or even black exhaust.

Frequent malfunction: the engine does not pick up speed and what should the driver do

If the engine stopped gaining speed, then the first step is to analyze when and how it manifested itself. In other words, the unit stopped spinning unexpectedly, or the problem with a set of revolutions gradually progressed. You should also pay attention to the presence or absence of other symptoms.

The fact is that the failure of a previously serviceable engine to gain momentum after carrying out any repairs or other manipulations may simply be the result of assembly errors, an unconnected sensor, etc. In such cases, the malfunction can be determined faster and more accurately after an independent inspection or an immediate return of the vehicle to the service, where the car was previously repaired.

Why the motor is not picking up speed: from simple to complex

At the very beginning, we will consider simpler and more obvious faults. The set of revolutions while driving is strongly influenced by the feed efficiency, the timeliness of ignition and the usefulness of combustion, as well as the composition of the fuel-air mixture.

A common reason when the engine does not pick up speed (injector, carburetor, diesel, gas car) is problems in the ignition system, as well as in the air and fuel supply systems. Experts point out the following:

  • Heavy contamination of the air filter reduces the ability of air to penetrate the filter element, as a result of which the engine becomes uneven, the unit loses power and does not pick up speed. Also, a common cause of problems with the air supply can be the fact that a foreign object (rags, plastic bag, etc.) may accidentally become in the air filter housing.
  • You should also pay attention to the suction of excess air at the intake as a result of various defects in the intake system. The problem can appear both unexpectedly and gradually progress. Note that the motor usually does not pick up speed in the event of a strong air leak. The fact is that in the composition of the fuel-air mixture, the normal ratio of air to fuel in such a situation deviates significantly from the norm. The mixture turns out to be very “poor” (a lot of air and a minimum of fuel). On such a charge, the engine starts, but does not gain momentum while driving, and also works intermittently.
  • A similar picture can be observed when the required amount of fuel is not supplied to the unit. The culprit may be the fuel filter, which can also become very clogged. Note that there may be no problems with starting the engine, since there is enough fuel for the XX mode. In parallel with this, while driving, the car may jerk, react to pressing the gas pedal with a long delay, when speeding up, dips may occur or the unit may not spin above any mark on the tachometer.
  • A dirty filter mesh of a gasoline pump can lead to similar symptoms. Deposits from the fuel tank tend to accumulate on the specified filter over time. As a result, the fuel pressure in the system becomes insufficient, the pump performance drops, and the motor itself is not able to operate normally in different modes. It often happens when the engine picks up speed and stalls precisely because of a clogged grid.

Now let’s talk about problems that may require certain knowledge, skills and equipment for diagnostics, and also be a reason for a visit to a car service. To begin with, this list of faults usually includes those when the engine does not pick up speed due to the failure of any element of the ECM, ignition system, power supply, etc. In other words, we are no longer talking about “consumables” (candles, wires, filters, pipes), but about details. In parallel with this, it should be considered whether the breakdown occurred unexpectedly or the malfunction progressed gradually.

  • One of the reasons may be knocked down timing phases. Violations of the synchronous operation of the gas distribution mechanism relative to the intake and exhaust strokes lead to the fact that the intake and exhaust valves do not open in time. The malfunction occurs as a result of errors during the timing belt replacement, if the specified timing belt has jumped one tooth or more teeth. Also, the cause may be incorrectly adjusted valves (the problem does not manifest itself sharply), various malfunctions in the systems for changing the valve timing, breakdown of the timing chain drive, etc.
  • Unexpected breakdowns include the failure of the ignition module, as well as malfunctions of the ignition coils. In this case, cylinder misfires begin, the engine troit and loses its ability to gain speed normally.
  • In situations with engine speed, the power supply of the injection nozzles should be checked. If there are problems with the wiring, then the control signal is not supplied to the injector or is intermittently received. As a result, the injector does not open in a timely manner, misfires occur in one or more cylinders, the engine does not pick up the required speed and loses power.
  • A fuel pump or fuel injection pump on diesel engines may fail. This malfunction usually does not occur immediately (unless the electrical wiring to the pump is damaged). Much more often, the drop in pump performance is gradual. Sooner or later, the pump will start pumping fuel very weakly, the pressure will be enough only for operation in the XX mode. An increase in load and speed will lead to the fact that the engine may stall under load, not spin up, etc.
  • In some cases, severe contamination of the injector itself leads to similar results. Driving on poor quality fuel, as well as ignoring the necessary cleaning procedure for the injectors every 30-40 thousand kilometers traveled may mean that the performance of one or more fuel injectors has dropped significantly.
  • The engine speed can also be affected by the state of the EGR system, the throughput of the catalyst or particulate filter. As for the second case, exhaust gas evacuation worsens through a clogged catalyst, the engine literally “suffocates” and is not able to pick up normal speed.
  • In parallel, it is necessary to check various sensors of the electronic engine management system. Their incorrect operation can affect the composition of the mixture, that is, the amount of fuel and air supplied to the internal combustion engine. These sensors include DPDZ, DMRV and a number of others.

Why the engine is not picking up speed well

During the operation of a gasoline or diesel engine, the driver may be faced with the fact that when the gas is pressed, the engine does not pick up speed. Note that after installing LPG equipment on a car, such a problem often arises when the engine on gas does not pick up speed, although the car runs normally on gasoline. Malfunctions of various kinds can cover both fairly simple things and indicate the need for serious repair of the internal combustion engine. Next, we will consider why the diesel engine does not pick up speed or the gasoline engine refuses to spin up.

What is the bottom line

Considering that there are a lot of reasons for problems with a set of revolutions on a modern car, it is optimal to immediately connect the car to diagnostic equipment (scanner) to search for possible errors. This is especially necessary to do in the case when the engine does not pick up speed and the check on the dashboard is lit.

Such failures are associated with a software failure in the operation of an electronic device. The ECU mistakenly assumes low speed (for example 2-3 thousand rpm) for the so-called “cut-off” speed and stops the fuel supply. In other words, the conditional protection against exceeding the permissible number of maximum engine speed is triggered prematurely.

Finally, I would like to add that timely cleaning of the injector, replacement of spark plugs and ignition wires, filters and filter elements of the fuel pump, cleaning the throttle valve, correct throttle adjustment and a number of other service procedures will allow you to get the maximum power from your internal combustion engine. As for cars with LPG equipment, not only the engine power and its gas revolutions, but also the overall service life of the power unit will depend on the correct installation and adjustment, as well as on the timely replacement of filters and maintenance of other elements of gas equipment.