What are the reasons for the loss of power of a gasoline engine. Typical malfunctions of electric motors and methods for their elimination A sharp drop in engine power

I welcome you friends to the DIY car repair site. A good car enthusiast knows the capabilities of his "horse" and its potential on the road. That is why any drop in engine power immediately catches the eye.

Another thing is that it is not so easy to determine the cause of this phenomenon. In this article, we will consider the problem from all sides and highlight the main causes of engine power loss.

Common engine power loss problems

In most cases, a decrease in traction is caused by the following reasons:

1. Poor fuel quality. If the car lost its power immediately after leaving the gas station, then the cause of the problems is the poor quality of gasoline. The result is a loss of power when the engine is hot. In the worst case, there are problems with the plant of the power unit.

The only way out in this case is to completely drain the old and fill in new fuel. If this is not done, then you can completely ruin the power unit.

The main symptom of bad gas is not only the loss of engine power. Often the problem pretends to be difficulties with starting, the appearance of soot on the contact group of candles and a reddish coating on their “skirts”.

2. Clogged air filter. Often the engine does not develop full power for a simpler reason - due to pollution. air filter . It is easy to explain this - the air-fuel mixture enters the engine without a sufficient amount of air, which worsens the quality of its combustion. As a result, the agility of the power node also falls.

The easiest way to solve the problem here is to install a new filter element. As a rule, it costs mere "penny", and you can make a replacement yourself and without involving expensive specialists.

3. Dirty or old spark plugs. If you have not changed the spark plugs in the engine for a long time, then you should definitely do it. Dirty spark plug electrodes, excessive wear, gap changes can all affect the quality of ignition and the efficiency of combustion of the air-fuel mixture.

In this case, you need to do two things - figure out what are the reasons for the contamination of the candles (if they have changed recently) and install new ones.

4. Clogged fuel filter. Some beginners are not even aware of the existence of such a device. In fact fuel filter plays a key role in engine performance.

If the device is clogged with various "garbage", then a limited amount of fuel will flow to the engine. The result is a sharp decrease in power. In this case, the best solution is the usual replacement of the fuel filter.

5. Problems with the engine on the mechanical side. In the worst cases, the reason for the decrease in power is a malfunction of the power unit itself - a decrease in compression, wear of piston rings, a change in valve clearance, and so on. In such situations, you can not do without a trip to the specialists and engine repair.

6. Fuel system. Another reason for reducing the thrust of the power unit is a malfunction in the fuel supply system. Here we are talking about a whole group of problems:

• Oxygen sensor malfunctions or injector;
• fuel pump failure. For example, due to the low quality of fuel or the retraction of gasoline from the bottom of the tank (this is where most of the dirt settles);
• depressurization of pipes and hoses through which fuel is supplied, and so on.

7. Contamination of the catalyst and exhaust system also one of the reasons for reducing the thrust of the power unit. To eliminate the problem, it is necessary to replace the catalyst. At the same time, you need to be prepared for certain expenses, because such a detail can be very expensive.

Loss of engine power on the injector and carburetor

When looking for a reason for reducing the thrust of a power unit, one must take into account the type of the engine itself - carburetor or injection.

Consider the probable malfunctions for each of the options:

1. The loss of power of the injection engine may be caused by the following reasons:

• Air or fuel filter contamination;
• low pressure, which is created by the fuel pump;
• contamination of the fuel pump grid;
• malfunctions of the car ECU;
• nozzle contamination;
• breakdown of the main sensors associated with the operation of the power unit;
• failure of the fuel pressure regulator;
• malfunction lambda probe and so on.

2. With a decrease in the power of the carburetor engine, the reasons may be as follows:

• Dirty fuel pump fittings or low pressure;
• carburetor contamination or needle valve problems;
• errors in the regulation of the composition of the air-fuel mixture;
• insufficient opening of the carburetor dampers;
• economizer valve sticking;
• decrease or excessive overestimation of the fuel level in the engine (may be caused by a malfunction of the float element);
• deterioration in the throughput of jets and carburetor channels, and so on.

When the first problems with the traction of the power unit appear, it is necessary to make a complete diagnosis, determine the cause of the malfunction and be sure to eliminate it. Otherwise, the consequences can be the most unpredictable. Good luck on the road and of course no breakdowns.

Before you begin to understand the reasons for the decline in the power of automobile gasoline engines, you need to understand some points. Many motorists studying the description of their car and its characteristics have probably noticed that the power of a gasoline engine is always indicated with reference to the maximum crankshaft speed.

The fact is that, unlike diesel engines, the power of gasoline engines directly depends on the crankshaft speed, that is, the higher the speed, the more power the engine can “give out”. And if the engine, for some reason, cannot develop maximum speed, then it will not develop full power.

The reason for the decrease in crankshaft speed may be overheating of the engine, which often happens in the summer or when driving in traffic jams. By the way, it is very dangerous and should not be allowed.

Loss of engine power - causes

1. A possible cause of a drop in engine power may be incorrectly selected spark plugs according to the glow number. You need to install only those candles that the manufacturer recommended in the car's user manual. Before installing the candles, do not forget to check and correctly set the spark gap between the electrodes of the candles.

2. When checking the spark plugs, at the same time pay attention to the high-voltage wires of the ignition system - worn and damaged wires can also cause loss of engine power.

To check the wire, you can remove it from the candlestick and bring it to the body of a running engine. Look at the color of the spark that jumps between the wire and the motor housing. The spark should be blue, if it is orange or red, then a wire breakdown or other ignition problems can be suspected.

3. As for the ignition system, in addition to a weak spark, a drop in engine power may be due to an incorrectly set ignition timing. Check the installation of this angle, in accordance with the instructions for the car, and if it is difficult for you, then contact the service station specialists.

4. In modern injection engines with a fuel injection system, the ignition timing is set automatically, that is, the on-board computer controls this process, and if problems arise in the electronic control unit, then you definitely cannot do without specialists.

5. For carbureted engines, problems can occur if the carburetor is adjusted incorrectly, for example, the fuel level in the float chamber is too high or too low, the accelerator pump is faulty, or the jets are clogged.

6. A clogged air filter, blocking the "breathing" of the engine, is also the cause of a drop in power.

7. In addition, the reasons why the engine does not develop full power can be the most elementary, for example, such as incorrect adjustment of the accelerator pedal stroke, due to which the throttle valve does not open fully or the use of low-quality gasoline.

In principle, there are not so many such reasons and most of them are eliminated without much effort.

Many at least once had to deal with a situation where the engine that worked perfectly before was “blown away”, the car seemed to grow an anchor from behind. The reasons why the engine does not pull and does not gain momentum are various, but it is not difficult to recognize the signs of the majority even without the skills of an automobile diagnostician or minder.

Common causes for all engines

The characteristics of the motor specified in the passport data of the car are provided under certain conditions. This is the filling of the cylinders with air, which is the working fluid in the internal combustion engine, corresponding to the norm. This is also the opportunity to heat it up to the required temperature in time - to supply a certain amount of fuel of the proper quality and set it on fire in time (the pressure peak for maximum efficiency should occur at the moment the piston passes top dead center).

ICE duty cycle

The loss of engine power, regardless of its design, is the result of a number of common causes. Let's start with fuel: its quality remains lottery, while the engine is tuned to a certain grade. That is, the mixture prescribed in the injection maps or specified by the carburetor settings can deviate from the ideal one, and the burning rate of the mixture changes. So, if problems appeared immediately after refueling, you yourself understand which way to look.

Filling the cylinders with air is rigidly connected with the valve timing. It is enough to leave the marks, as the cycles of the internal combustion engine will be shifted: already a difference of 1 tooth can significantly reduce the power of the motor. Moreover, it is not necessary for a belt or chain to jump - more and more motors receive keyless pulleys, which require rigid fixation of the shafts with special devices during installation. If you do not reach the pulley, and one day it will move from a given position. And it’s good if the engine simply loses traction, and does not hit the piston on the valves that did not close in time, driving them into the cylinder head.

For engines with variable valve timing, the camshafts (at least one) have the ability to shift so that, with sufficient throttle response at the bottom (small phase overlap), they do not lose at the top (the camshafts move “toward each other”, increasing the overlap phase, which at high speeds increases power ). Possible reasons why the machine does not pick up speed is a failure of the VVTi control valve or problems with the phase shifting clutches. We have already discussed this issue, speaking about.

In addition, the filling of the cylinders is tied to the intake and exhaust resistance. It is necessary to manage to clog the air filter so that it loses its capacity, but oil emissions through the crankcase ventilation system, especially if the piston is already worn out and the oil catcher is primitive, are not uncommon. On the VAZ-2106, it is not difficult to make the engine “sip oil” through the crankcase ventilation, and such cases are possible on fresh front-wheel drive cars (2109, 2110, 2114). An oily air filter has a sharp increase in resistance, hence the loss of engine thrust.

The release on carbureted cars and old diesel engines is simple, and it is enough to reduce the flow area so that the engine begins to “choke” on exhaust gases, except perhaps with a powerful blow (when moving over bumps, for example) or a canonical potato - but it is at least immediately noticeable.

If the engine with electronic injection does not pull, then the catalyst falls under suspicion in this case. Overheating, fuel ingress due to malfunctions of the power system can cause sintering of its cells. For diesel engines with particulate filters, soot becomes the main enemy: automatic filter burning on the go is ineffective, and at least forced regeneration must be performed.

Problems with the release easily give themselves away: a muffled engine, on a subsequent attempt to start, throws smoke into the intake, the sound of the engine changes, leaks immediately “crawl out” (the exhaust begins to “cut” to the damaged area).

The motor must not only receive the right amount of air and fuel - it must ignite in time. A gasoline engine needs an appropriate ignition timing, a diesel engine needs an injection timing. Since there is no separate ignition system on modern injection engines, ignition timing problems are primarily characteristic of carburetor machines and old injection systems with a distributor (the Japanese used such systems right up to the early 2000s). Check the basic advance angle, set by the distributor, and the operation of the advance automatics in it (in case of malfunctions, the angle that is normal at idle will begin to “leave” when revving).

A separate case is motors where the distributor is driven by a separate pulley from the timing belt (old Audis and Volkswagens). Here, when replacing the belt, the distributor pulley is set “as it should be” (there are no marks on this pulley!), Forgetting that the distributor must be oriented with a cam at the risk on the crankcase under it when replacing the belt. After such a replacement, the car stops driving, as the ignition angles change. For diesel engines with a mechanical injection pump, the initial injection angle is set, in addition, the advance regulator works - they are checked according to the data from the repair and maintenance instructions.

On gasoline engines, we also add spark plugs to the suspects: even if the engine runs normally at idle, it is not a fact that the spark plugs will work well under load, when the pressure in the cylinders at the end of the compression stroke increases and the conditions for sparking become worse. It is worth putting another kit for testing: without an oscilloscope that allows you to take voltage curves from a working ignition system, it is difficult to determine how the candle actually behaves under load. In the illustration below, look at the peak voltages corresponding to the moment of sparking: in the third cylinder, the gap is excessively increased, the spark flares up at too much voltage, and its duration drops (the power accumulated in the ignition coil is not enough for normal spark burning).

If we talk about compression, then under normal conditions it decreases as it wears so slowly that the decrease in power occurs imperceptibly for the driver. An exception is rapidly developing breakdowns (cracks in piston rings, destruction of partitions between rings,). Simultaneously with the drop in power, the stability of idling will drop sharply, the final diagnosis will be unambiguously made by a compression gauge.

As for turbocharged engines, the state of the turbocharger is reflected well in their dynamics. An ideal centrifugal pump (turbocharger impeller) has a quadratic dependence of performance on speed: once the speed drops by half, the boost pressure will drop by four. Wedging of the rotor due to destruction or coking of the bearings, burning of the “hot” impeller is the probable reason why the turbocharged machine does not pull. Here, as with compression, a pressure gauge will help out.

Causes of power loss in a carburetor engine

Here it is worth immediately checking the fuel level and the operation of the fuel pump: “underfilling” the fuel immediately betrays itself under load with a loss in dynamics, shooting through the carburetor. Overfilling due to a faulty carburetor locking needle will in the same way lead to a loss of power by the engine, here black smoke and firing from the muffler will become a characteristic feature.

The dynamics of the car is perceived better during acceleration, so a defect in the accelerator pump can also become a possible cause of the “stupidity” of the car. The fact is that all carburetor systems are designed to work in static modes, while the mixture becomes leaner when the speed is set. An accelerator pump serves to combat this over-depletion: when you press the gas pedal, the diaphragm pushes a dose of gasoline through the shut-off valve into the atomizers that go into the diffusers. If the diaphragm of the accelerator pump is broken or the sprayers are clogged, the acceleration of the car will immediately deteriorate so much that it is hard not to notice. It is not difficult to check the accelerator pump - after removing the air filter or the "turtle" from the carburetor, you need to sharply press the throttle actuator: your fingers will feel resistance (the diaphragm will create pressure in the accelerator pump), and gasoline streams should hit the inlet from the atomizers.

In operating modes, the composition of the air-fuel mixture is set statically by a set of fuel and air jets. It is worth blowing them out, and in case of noticeable deposits, rinse with a cleaner: even if this is not the problem, it will not be superfluous to maintain the health of the main dosing system.

Does not pull injection engine

Why doesn't the car pull when the injection systems are feedback-capable and can self-adjust in a "closed loop"? Alas, the possibilities of self-regulation are not as wide as we would like.

The first enemy of injection systems is insufficient fuel pressure. When the fuel consumption is minimal, then the correction margin is enough for idling. But one has only to put a load on the engine, as the correction will jump to the limit threshold, but the nozzles will still “underfill”.

The pressure in the fuel rail is set by three nodes: the fuel pump itself, the pressure regulator and a set of filters (coarse and fine cleaning). The performance of a serviceable fuel pump is several times greater than the needs of the engine at maximum flow - this is done so that the wear of the pump affects the operation of the engine as little as possible. Therefore, a fuel pressure regulator is used, which dumps "excess" fuel either immediately at the pump outlet or from the fuel rail after the fine filter.

In the first case, the fuel rail is called drainless (16-valve VAZ engines, modern foreign cars), in the second - drain. The difference between these systems is in the location of the regulator and in its operation. On the drain ramps, the pressure regulators are controlled by a vacuum in the intake manifold, the pressure in the rail varies depending on the load (at normal 3 bar for VAZ at idle, it is 2.3-2.4 bar, take this into account when diagnosing!). On drainless, the pressure is maintained constant relative to the atmosphere and, depending on the model of the car, is 3.5-4 bar. An exception is direct injection systems, where the operating pressure ranges from 20 to 70 bar.

Something else useful for you:

The resistance of the fuel filters does not affect when measuring the fuel pressure "in the plug" (the pump is forced to turn on with the engine turned off when there is no fuel flow in the rail) and is minimal at idle. But on the other hand, under load, an excessive increase in the resistance of the filters reduces the fuel supply to the rail, which will lead to a loss of speed. Therefore, measure the pressure at idle and under load (for example, by hanging the drive axle and braking the wheels in gear). In cases where idling is normal, and the problems are on the go, it is pointless to measure pressure only at idle (XX).

Check exception steps:

1. Remove the coarse filter ("mesh" at the inlet). For a number of machines, this is a well-known problem - for example, on the second generation of Focuses.
2. Replace fine filter.
3. Measure pressure under load.
4. On engines with a drain rail, pinch or otherwise shut off the return line to eliminate the influence of the fuel pressure regulator. On engines with a drainless ramp, the RTD is installed in the fuel pump module, here it is easier to temporarily install a plug washer made of polyethylene or other material that is not destroyed by gasoline under it.
5. Measure the pressure again: if it has increased, then the RTD needs to be replaced, otherwise the pump needs to be replaced.

The second reason for "underfilling" is. Even with normal filter operation, deposit formation on atomizers is inevitable over time. It is possible to evaluate in “home” conditions only the shape of the spray jet by removing the ramp and turning the motor with a starter (Attention! This procedure is a fire hazard!). A clean nozzle should “dust” evenly, and not give separate streams or pour to the side. It is possible to evaluate the performance of injectors and compare it with the nominal one only at the stand.

The loss of dynamics is a consequence of excessive enrichment of the mixture. The fuel pressure regulator cannot be blamed here (pump performance, even when operating without an RTD, is not so high that the correction margin of the injection ECU does not block enrichment). It is much more likely that the injectors are leaking (again, it is checked at the stand) or the failure of the sensors that are used to calculate the injection time.

Here, the undisputed leader is the mass air flow sensor - an accurate but sensitive device. As the DMRV becomes dirty and aging, it overestimates the readings, the car begins to consume significantly more fuel. As a result, the over-enrichment of the mixture can no longer be corrected for. But such a malfunction is immediately visible: the car will begin to smoke, the candles will become overgrown with black soot. On motors with an absolute pressure sensor, the air temperature sensor is more likely to fail (here it is a separate unit, while it is built-in in the DMRV).

On cars with an electronic throttle, it is worth checking the operation of the servo by removing the nozzle from the throttle and giving it a gas flow. The throttle should open evenly, without pauses and wedging, indicating problems with the drive gearbox or (the axis, acquiring soot, wedging in the housing).

Video: Lost power. Loss of power

Seal

During the operation of the car, many owners face a number of problems. One of them is a decrease in engine power. At the same time, it is not always clear what is the reason for this phenomenon, what measures to take, whether it is worth going to the service station. Let's talk about the main reasons why the engine does not pull and how you can fix the problem on your own.

The main reasons for reducing engine power

1. Malfunction of the crankshaft position sensor

There are situations when the DKPV does not send a control command to supply the air-fuel mixture in a timely manner. As a result, the power of the power unit drops before our eyes. The main reason for the failure is the shift of the gear star in relation to the pulley and the bundle of the damper. In such a situation, it is necessary to carefully inspect the damper and replace it.

2. Increase (decrease) the gap between the electrodes of the candles

During operation, due to the powerful temperature effect, the distance between the electrodes of the spark plug may decrease or increase. To exclude or confirm your suspicion, you need to check the size of the gaps with a round feeler gauge. If the distance is less or more than the allowable one, you need to adjust by bending the side of the electrode or replace the spark plug. As for the optimal distance of the spark gap, it can be different (depending on the type of candle) - 0.7-1.0 mm.

3. The appearance of soot on candles is another clear sign of a problem.

If the engine does not pull well, it is necessary to unscrew all the spark plugs one by one and inspect them. If obvious carbon deposits appear on the electrodes, the device must be cleaned with a brush with a metal bristle. It is important not only to clean the candles or replace them, but also to find out the cause of this phenomenon.

4. Failure of spark plugs

Reduced engine power may be caused by product failure. In this case, it is necessary to check the performance of the candle on a special stand. If the suspicions are confirmed, then the only way out is to replace the set or one candle.

5. There is no gas in the tank

You can diagnose the problem by looking at the fuel gauge. If it is faulty or there is a suspicion of its “inadequacy”, then the presence of fuel can be determined by removing the fuel pump.

6. Fuel filter contamination, water freezing in the system, fuel wire pinching, fuel pump failure

All these malfunctions can be safely attributed to one category, because they all have the same symptoms - the starter cranks the engine, but there is no smell of fuel from the exhaust pipe. If the car is carbureted, then the cause must be sought in the float chamber. Most likely it is not getting fuel. In the case of an injector, the presence of fuel in the rail is easier to check by pressing a special spool (installed at the end of the rail).

To correct the problem, it is necessary to warm up the engine thoroughly and bleed the power system with a tire pump. After that, all the pipes of the system, hoses and the fuel pump itself are changed.

7. The fuel pump creates too little pressure

Such a problem can only be determined by special measurements (made directly at the outlet of the fuel pump). After that, the quality of the fuel pump filter is checked.

The solution is to clean the fuel pump filter, replace it (if repair is not possible) or install a new fuel pump.

8. Poor contact quality in the circuit

Poor quality of the contact in the circuit through which the fuel pump is powered or the failure of its relay. The first thing to do to check is to make sure the quality of the "ground" on the car and take resistance measurements with a multimeter. If the resistance level is really high, then the only way out is to strip the contact groups, crimp the terminals well or install a relay (if the old one is faulty).

9. Broken nozzles or malfunction in the supply system

If there is a suspicion of failure of these elements, it is necessary to check the resistance of the windings with a multimeter for the fact of an open circuit or an interturn circuit. If the cause of the problem is a malfunction of the computer, then such a check can be carried out exclusively at the service station.

There are several ways to eliminate the decrease in engine power for this reason (depending on the depth of the problem) - install a new computer, clean all nozzles, ensure high-quality contact in the electrical circuit, and so on.

10. Breakdown of the DPKV

Breakage of DPKV - crankshaft position sensor or damage to its circuit. In such a situation, the check engine malfunction lamp lights up. The first thing to do is to inspect the integrity of the DCPV itself, make sure that the gap between the ring gear and the sensor is normal (it should be about one millimeter). The normal resistance of the sensor coil is about 600-700 ohms.

To solve the problem, it is enough to restore normal contact in the electrical circuit and install a new sensor (if the old one turned out to be faulty).

11. Out of order DTOZH

DTOZH - a sensor that controls the temperature of the coolant is out of order. Symptoms of a malfunction are as follows - the engine malfunction lamp lights up. If there is a break, then the electric fan of the system begins to rotate continuously. In addition, it is necessary to check the health of the sensor itself.

If the engine power has dropped for this reason, then it is necessary to restore the quality of the contact in the electrical circuit and install a new sensor.

12. Out of order TPS

The TPS is out of order - a sensor that controls the correct position of the throttle valve (or its chain). As in previous cases, the “Check engine” lamp lights up here. If there is an open in the TPS circuit, then the engine speed usually does not drop below one and a half thousand revolutions.

The solution to the problem is to clean the throttle assembly and restore the quality of the contact connection in the entire electrical circuit. If the sensor is defective and cannot be repaired, it must be replaced.

13. Out of order DMRV

The DMRV, a sensor responsible for controlling mass fuel consumption, failed. Here, the optimal action is to check the integrity of the DMRV or replace it with a serviceable device. If the failure of the DMRV is confirmed, then it is necessary to make an attempt to clean it, and if it is impossible to repair, simply replace it.

14. Breakage of the knock sensor

Detonation sensor failure. With such a malfunction, the engine malfunction lamp necessarily lights up on the instrument panel. In addition, when DD detonation fails, there is no detonation in any of the operating modes of the power unit and the engine power also drops. With such a problem, the best option is to restore the integrity of the contact group in the electrical circuit and install a new sensor.

15. Failure of the oxygen sensor

Failure of the oxygen sensor or a violation of its circuit. Such a malfunction is characterized by the ignition of the "Check engine" lamp. In this case, the first thing to do is to check the heating coil for integrity. Firstly, the resistance is measured, and secondly, the voltage level at the output. Measurement can be done even without breaking the circuit - just pierce the insulation with needles.

To eliminate the malfunction, it is worth repairing the oxygen sensor, restoring the quality of the wiring and cleaning all the holes through which air is sucked in. In extreme cases, it is necessary to replace the oxygen sensor itself.

16. Depressurization of the exhaust system

Diagnosing such a problem is simple - just inspect the main elements while the engine is running at medium speeds. To solve the problem, it is necessary to replace the exhaust manifold gasket and stretch all the seals.

17. Computer failure

Failure of the electronic control unit (ECU). Despite its reliability, the ECU can also break down (sometimes its software just gets lost). To make sure that the computer is working (failure of the computer), you need to check the voltage on the unit itself (the normal parameter is about 12 Volts) or replace it with a known-good unit. If the control unit is defective, it may need to be replaced. In some cases, it is enough to change only the wiring.

18. Violation of the adjustment of clearances in the valve drive

You can make sure that the parameters match only by checking with special probes. If the gaps do not correspond to the norm (written in the manual), then adjustments must be made.

19. Deformation or breakage of the springs on the valves

In this case, you will have to remove the cylinder head and measure the length of the springs under load and in a free state. If broken or deformed springs were found, then they need to be changed.

20. Worn camshaft lobes

Here it will be enough to visually inspect (after removing the necessary elements) and replace the camshaft if necessary.

21. Disordered valve timing

In such cases, it is necessary to check the fact that the marks on the camshaft and crankshaft coincide. If there is an “imbalance”, then it is enough to set the correct position using special marks.

22. Low cylinder compression

Low compression in all or some cylinders. Causes include likely valve damage or wear, broken or sticky piston rings. To verify the suspicions or refute them, it is enough to make the necessary measurements. If the suspicion is confirmed, then it is necessary to repair the power unit - change the rings, pistons or repair the cylinders.

Conclusion

The above list is only a part of the malfunctions, due to which the engine power drops. But in most cases, this is enough to diagnose the problem, fix it, and return much-needed traction to your “iron horse”.

Sometimes when driving a car, the driver notices strange things - the car picks up speed more slowly, consumes more gasoline, the engine is heard better. This is most likely due to power loss. There can be many reasons why the engine does not develop proper power.

How to understand that the engine power has dropped

This is usually felt immediately by the following symptoms:

• The car accelerates more slowly;
• Fuel consumption increases;
• You have to “turn” the motor more in order to somehow accelerate. Engine performance is worse.

Checking indicators on the stand + video

To accurately verify the drop in power, the car must be sent to the power stand. Typically, such devices can be found in car services, tuning shops or dealerships. You can see how this happens in the video.

Reasons for declining engine performance

Change the gas station for a while and watch the agility of the car. Possibly a bad fuel problem.

The appearance of a problem on gasoline (carburetor or injector)

In the case of a gasoline carburetor engine, the reasons may be as follows:

• early ignition. The fuel mixture ignites prematurely, the force of the exhaust gases resonates with the direction of piston movement, resulting in reduced power.
• Late ignition. The mixture does not have time to burn out for a full cycle of the engine, which means that it does not develop the necessary power.
• Problems with the vacuum ignition timing controller. Found only on carbureted engines!
• Problems with the centrifugal ignition timing controller. They also lead to early ignition.
• Loose fit of valves in their saddles.
• Worn piston rings.
• Throttle stuck.
• A large amount of carbon deposits in the cylinders.
• Intake manifold clogging.
• Using fuel with the wrong octane rating.
• Lean working mixture caused by air leakage, fuel line contamination, air duct clogging;
• Clogged filters.
• Clogging of jets or carburetor fittings, incomplete opening of its dampers.
• Water entering the carburetor.
• Incorrect adjustment of the composition of the fuel mixture.

In the case of an injection engine:

• Clogged fuel and air filters.
• Problems with the electric fuel pump.
• Incorrect operation of the electronic control unit (ECU) of the engine.
• Problems with fuel injectors.
• Incorrect operation of sensors.
• Faulty lambda probe.
• Injector failure.
• Carbon deposits in the cylinders.
• Worn seals, gaskets, rings.

Why the diesel engine does not develop the desired performance

• Poor quality fuel.
• Fuel filter clogged.
• Clogged air filter.
• Failure of the turbocharger (extremely important these days - atmospheric diesel engines are almost never found. Check the quality of the turbines).
• Malfunction of fuel injectors.
• Clogged particulate filter.
• Clogged fuel pickup in the gas tank.

Detailed video about the causes of power loss

Poor throttle response due to clogged catalytic converter

As you know, power can be lost due to the contamination of the catalyst located in the muffler. How to check it?

• Measure the pressure in the exhaust system. If the value obtained is greater than 0.5 atmospheres, the catalyst needs to be replaced or removed.
• Having warmed up the engine well, measure the temperature of the exhaust pipe before and after the catalyst. If the temperature before and after is the same, the catalyst is clogged. Similarly, if the temperature after is lower.
• Ringing inside the catalytic converter.

In case of problems with the catalyst, do not remove it without subsequent replacement. Extraneous noise and the overall noise of the engine will increase, the resonance of the exhaust system will be disturbed, and this practically does not affect the engine power. It is better to install a new catalytic converter than to drive without it.

Ways to increase engine power

• Refuel with higher octane rating than recommended.
• Replace the standard air filter with a zero resistance filter.
• Replace the standard exhaust system with a direct flow.
• Engine chip tuning.
• Replacing engine oil with a better and less viscous one.

Loss of engine power is an annoying problem for any motorist. The car does not drive as it should, and sometimes it is very annoying, and sometimes it is not safe at all, so finding the root causes and eliminating them is an important and necessary task. Good luck on the roads!