Hydraulic lifters are knocking, what should I do? Priora 16 valves

Causes of knocking hydraulic compensators

Engine knocking when starting. If the extraneous noise disappears a few seconds after starting the engine, this is not a sign of a malfunction.
There is a knocking sound from hydraulic compensators on a cold and warm engine, the noise disappears when the speed increases. The check valve ball may be worn out and the hydraulic compensator will have to be replaced. It is also possible that the hydraulic compensator mechanism may become dirty; cleaning the parts will help.
The knocking noise only occurs when the engine is warm. Wear and, as a consequence, the appearance of increased gaps between the plunger and the hydraulic compensator sleeve. You will have to change the hydraulic compensator.
Engine knocking at high speeds. The cause may be too much or too little engine oil. Bring the engine oil level to normal. It is also possible that the oil receiver may be damaged, in which case the faulty parts should be replaced.
The valves are constantly knocking. The reason may be a gap between the pusher and the camshaft cam. Cleaning or replacing faulty parts will help.

Hydraulic compensators and “Accent”

The reasons for the knocking are standard here. The owners write that the problem can be solved by changing the oil. More experienced owners believe that if hydraulic compensators knock when cold (Accent is no exception), this is nothing more than a feature of the engines.

But in general, most drivers change oil with a viscosity of up to 5W30, and this allows you to completely get rid of the knocking of these mechanisms in the engine.

Basics of the design and operation of a hydraulic compensator

Configuration

The idea of automatic regulation of thermal clearances can be implemented in two versions: a conventional hydraulic pusher and a hydraulic support. The latter is used in gas distribution modules with rocker arms. On the Lada Priora in the sixteen-valve version, the intake and exhaust are equipped with individual camshafts. The optimal solution for this arrangement is the use of a hydraulic pusher.

Procedure for replacing hydraulic compensators

Replacing this part with a new one is a simple procedure that you can do yourself; the make of the car in this case is not so important, since the design of the engine and the principle of operation are similar for all power units. The only difference is that when replacing the compensator on some models, the cylinder head cover gasket must also be changed. But, in general, the principle of replacement is the same, so you should consider replacing this part as a whole.

Remove the valve cover.
Remove the sprocket from the camshaft. This is done using wire. You just need to hook the part and lift it up.
Check the tensioner and damper. If they are too worn out, they should be replaced with new ones.
Remove the fasteners from the crankshaft and remove the bed.
Remove the rockers and place them in a certain sequence. You can arrange them by number to avoid confusion.
Remove the expansion joints one by one. When dismantling different parts you will have to apply different forces. This can be explained by vibration when driving. Hydraulic compensators are also located by numbers if they are planned to be cleaned and diagnosed.
Rinse and clean the oil pipes and their installation sites.
Screw the hydraulic compensators into place. Care should be taken during installation, as applying great force may damage the part. Therefore, it is advisable to use a wrench with a dynamometer.
After installation, you should install the removed parts according to the numbers reverse to removal.
It is imperative to secure the valves in place with a wide screwdriver.

Dismantled valves can be restored by washing them, but most often after replacement, no one washes the old parts.

This procedure is completely similar to replacing valves on a Niva Chevrolet. Other cars have minor differences. If you do not have sufficient skills or are not confident in your actions, it is recommended to contact specialized workshops.

If you are the owner of a car with n52 hydraulic compensators, then to remove extraneous sounds you just need to replace the oil with a more viscous one, for example 5W-40 oil. Such a replacement can correct the problem if the oil was to blame. If you drive your car too slowly, it will also ruin your car's engine. It is necessary to follow this commandment: slow acceleration with slow deceleration. This will help preserve the engine and also reduce fuel consumption.

Do-it-yourself replacement of hydraulic compensators on a Priora 16 valves:

Need advice on solving the problem of knocking hydraulic compensators on a Priora

Guys, the problem is this: the hydraulics were knocking on the Priora, I installed new ina brands, filled in new Lukoil synthetic oil 5w40, changed the timing belt, filter, rollers, but the knocking never stopped - the car runs cold like a diesel engine. There is no loss of power, the engine runs smoothly. MB anyone encountered this problem?

Maybe the problem is not in the hydraulics?

What knocks when a Priora 16 valve engine is hot?

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“Tenth” family (VAZ-2110, VAZ-2111, VAZ-2112) and LADA PRIORA

HELP I don’t know what to do.

remove the valve covers, measure the gaps, if everything is ok, then open the pan. and then according to the situation.

Hello. I have a problem, the engine was knocking. VAZ-21102, mileage 60,000 km. I filled it with Castrol synthetic oil, washed the engine with flushing oil and filled it with ZIk semi-synthetic. I hadn’t driven even 1000 km before I noticed a knocking noise. The knocking is not constant for two seconds, knocking for two seconds and so on, frequency The knocking noise is much lower than the crankshaft rotation speed, it does not knock on a cold engine, the knocking appears when the engine warms up to 50-60 degrees, and is especially loud on a fully warmed-up engine. The knock is metallic but not loud. It is heard only at idle speed at 800-1000, at As the speed increases, the knocking is not audible. Traction, dynamics and consumption are normal as usual. Specialist. He said that either the piston or the connecting rod was damaged, but he would be able to establish it for sure only after disassembling the engine. HELP I don’t know what to do.

On my previous car, VAZ 21099, I had everything exactly like yours:

periodic metallic knocking, and only when the engine is warm and at idle speed.

When opened, one of the pistons turned out to be bent.

Result: replacement of pistons and pins

I bought the car new, for maintenance, I didn’t spare money on consumables, I only filled it with synthetic Castrol.

maybe the hydrik died

I have a problem, the engine is knocking. VAZ-21102

The knocking is not constant for two seconds, it knocks for two seconds, no, and so on, the knocking frequency is much less than the crankshaft rotation speed, it does not knock on a cold engine, the knocking appears when the engine warms up to 50-60 degrees, and is especially loud when the engine is fully warmed up. The knock is metallic but not loud .Audible only at idle at rpm 800-1000, when the rpm increases the knocking is not heard

The camshaft rotates twice as slow as the crankshaft. Most likely a pusher. You need to take some long screwdriver, put it on different parts of the head and listen with your ear on the other side of the screwdriver. Or what is long and hard at hand, for example the handle of a shovel.

And by engine knock, they mean another knock. It cannot be confused with any knock.

Here, perhaps the new oil washed away the varnish deposits in the head, and something got too loose. This is usually how the pushers knock. And if this is so, then nothing bad will happen except a knock.

number 29

Nik77

I still think that it is the valve pusher that is knocking on its own, possibly the adjusting washer in the recess of the pusher. If there had been a knock from the large gap between the cam and the pusher, it would not have disappeared.

2. In the VAZ 21099/»>VAZ 21099i engine manufactured in 2001 (mileage 22 thousand km), one or two minutes after a cold start, extraneous sounds appear, reminiscent of detonation. They do not coincide with the frequency of the timing noise, which occurs at regular intervals, weakens as the engine warms up, and disappears when operating temperature is reached. At the service station, the gaps were checked - they were normal, and the extraneous noise was explained as a consequence of some modernization of the timing belt, which VAZ carried out recently. ZR magazine spoke about the modernization of the timing belt carried out by VAZ. A sphere is introduced on the inside of the pusher in the area of its contact with the end of the valve stem. This reduced the amount of lateral force acting on the valve and reduced the noise level

Timing belt and increased the service life of the guide bushings. On the VAZ 2110 and VAZ 2111 engines, a 2110 camshaft with an increased intake cam height appeared, which increased power by about 2 kW compared to the 2108 camshaft. However, upgrading the timing belt has nothing to do with extraneous noise from your engine. Most likely, this is a special case caused by some deviation from the requirements of the technical documentation. Obviously, it makes sense to conduct audio diagnostics of the engine using a stethoscope and localize the zone of “non-functional” sound. After this, you can look for a solution: partial or complete disassembly of the engine with inspection and replacement of parts is not excluded.

Pay attention to the words reduced the timing noise level

, i.e. It was bigger before and didn’t completely disappear.

You can add thicker oil and the knocking noise should disappear.

Valve knocking is usually a consequence of excessive clearances in the drive. It does not disappear when the speed changes smoothly. Conclusion: adjustment is necessary. But in the engines of front-wheel drive VAZ cars there is a source of similar mild knocking: the valve tappets sway during operation. The sound may come and go. This is an innate feature of the engine. However, harmless? Let's close our eyes to her.

The knocking noise of the engine does not go away or appears after warming up

Much more dangerous is the knocking of hydraulic compensators, which appears as it warms up or only intensifies as the power unit reaches operating temperatures. In this case, the hydraulic compensators constantly knock at idle speed of a warm engine; the knock may be present under load, etc. The list of causes for this malfunction is wider than knocking noises on a cold internal combustion engine.

First, you need to make sure that it is the hydraulic compensators that are knocking when hot, since there are many reasons for knocking in the engine. To do this, you need to know how to identify a knocking hydraulic compensator. It is also important to be able to determine which hydraulic compensator is knocking, which will help more accurately localize the fault.

Note that the knocking of compensators has a characteristic sound. The pitch is high, the knock is loud, reminiscent of a metal ball striking another metal part, and is localized under the valve cover. Can be easily heard with a stethoscope. If the main valve knocks constantly, then it may soon become completely jammed or other breakdowns will occur. In such a situation, the engine needs repair; it is possible to replace the hydraulic compensators. In some cases, the seat of the hydraulic compensator is also broken. After the motor heats up, thermal expansion of the parts occurs, and the hydraulic fluid begins to “dangle” at the installation site and knock. A more accurate determination of a knocking main engine is possible after partially disassembling the motor and removing the cover.

As already mentioned, on a cold engine, contamination of the channels can cause knocking, after which the extraneous sound disappears as it warms up. In the case of a hot internal combustion engine, exactly the opposite happens, when, parallel to the increase in temperature, the deposits in the channel soften and shift, completely blocking the supply of lubricant to the main fluid chamber. In this case, it is also recommended to flush the hydraulic compensators and lubrication system, change the engine oil, or clean the engine after disassembling it.

The oil filter should be checked, which may be the cause of insufficient pressure in the lubrication system and, as a result, knocking of the engine when hot. If there is insufficient pressure in the hydraulic compensators, an air lock is created. The oil level in the engine also deserves special attention, which should not be lower or higher than normal (oil overflow into the engine). It should be noted that when cold, at low speeds and problems with the oil level, the HA may not knock. After the engine warms up, the amount of air in the oil increases and a knocking sound from the hydraulic compensators appears, as the oil and air become a compressible mixture. It is also advisable to check the operation of the oil pump and measure the pressure in the lubrication system if problems with the hydraulic fluid appear on a hot engine.

How to eliminate the knocking of hydraulic pushers on Lada Priora

Timely and high-quality maintenance of the engine oil system is the key to flawless operation of the hydraulic compensator mechanism. After all, the unit is designed for use throughout the entire resource of the power plant.

Use of recommended lubricant

When the hydraulic pushers just start knocking, the manufacturer recommends changing the lubricant to a proven option. Therefore, when the question arises of what kind of oil to pour in principle, it is worth analyzing reviews to determine the acceptability of a certain model of oil product for hydraulic compensators.

Of course, the best choice for Lada Priora will be the composition recommended by the manufacturer, specified in the instruction manual. However, not all current popular products are included in the list.

An analysis of opinions shows that, indeed, with the universal viscosity of 10W-40 or 5W-40 specified by the factory, not every oil is suitable. For example, Shell Helix Ultra 5W-40 causes knocking already at 15,000 km, while on Liqui Moly Optimal Synth 5W-40 the hydraulics are silent even at 80,000 km.

Reviews show that it is optimal to choose the following lubricants:

Total Quartz 9000 Energy 5W-40.
Mobil Ultra 10W-40.
Wagner Windigo 10W-40.

Flushing

Many owners, in advanced cases, resort to general engine flushing. However, the effectiveness of such an event in the fight against knocking GCs is low. This is explained by poor oil pumpability in the area of the hydraulic pusher chambers.

If changing the lubricant does not help, the best solution is to remove the cylinder head cover and find which hydraulic compensators on the Lada Priora 16-valve engine are knocking and determine the reason for this. Defective parts are identified by diagnosing running resistance with a wooden wedge. A fast movement speed in comparison with other hydraulic supports indicates wear of the hydraulic module, the presence of a constant gap indicates its coking.

Attention! The wooden wedge must be pressed against the non-working surface of the cams.

Effective removal of carbon deposits inside the cylinders is their local washing. Worn assembly modules cannot be repaired.

Additives

Additive compounds help delay identifying the causes and cleaning the timing belt. There are several products available in the market. The most popular products are from Liqui Moly and XADO. The effectiveness of substances depends on the specific case. Fans of motor additives often equate this class of chemistry with a waste of money.

Everything should be nearby, don’t start without preparation

Lada Priora can serve as an example to consider the replacement process. To avoid unpleasant surprises, any work must be planned and everything necessary must be prepared. In our case we will need:

Gasket Maker - sealant (anaerobic);
camshaft plugs and seals;
16 INA compensators.

Let's start by disconnecting the battery minus. Then we dismantle the air filter, throttle cables, wires that will interfere with manipulation, injector ignition coils and intake manifold.

Replacing hydraulic compensators on a Priora is complicated by the fact that the manifold mounting bolt is located under the generator.

To get to the hydraulic compensators:

The generator belt is removed, the generator itself is freed from the mounting bolts and carefully moved to the radiator. Using a wrench with a rotary head, the manifold mounting bolt is unscrewed.
The ramp with nozzles is dismantled and the air conditioning pipes are disconnected (if equipped).
The collector is dismantled. First, we lift its left edge and then the entire part, and then we move it to the left.
The valve cover is removed using a screwdriver inserted into the technological grooves.
Next, the timing belt is removed, the pulleys, camshaft bed and the shafts themselves are dismantled.

We are taking action

So, the hydraulic compensators are knocking, what should you do? Do not panic. Such a phenomenon has not yet brought the car to exclusion from the transportation process.

The functioning of this important part is directly related to the lubrication system. If the hydraulic lifters are knocking, the likelihood that the oil has lost its original characteristics is quite high.

Don't immediately think about disassembling the engine. First of all, to eliminate knocking, change the oil and filter. After replacement, when starting, do not flinch from the knocking of the hydraulic compensators; during the process of draining the oil, it will leave them, and the plungers will fill when the oil pump starts.

If this does not help, then you need to find out which hydraulic compensator is knocking. The question arises, how to determine the one that needs to be changed? For example, the VAZ 2112 has 16 valves, how can you find out which one is not functioning?

To do this, you need to position the camshaft cam (rocker arm) so that it does not interfere and try to press the compensator with a drift. The serviceable one will press through if significant force is applied, the faulty one will go down easily. It needs to be removed.

Assembly nuances

After replacing 16 hydraulic compensators, everything must be restored to its original form. The most important operations in order:

We clean and degrease the camshafts and seats of the bed and valve cover, both on the parts and on the engine.
We change the seals, plugs and put both shafts in place. The inlet has a special belt, which is not present on the outlet. This is its distinctive feature.
Apply Gasket sealant to the mounting location of the camshaft bed and mount it (no gasket required).
We treat the fit for the valve cover with sealant and mount it (no gasket required).
We install injectors, condenser tubes, mount the manifold, generator, its belt, pulleys and timing belt.
We restore the operation of the throttle valve, filter and connect all the wires.

Replacing hydraulic lifters sometimes results in the engine not starting due to lack of compression. As a rule, hydraulic valves are installed oil-filled and it may happen that due to the incompressibility of compensators, some valves will be open. To avoid this, it is necessary to tighten them with a clamp before installation.

If, when starting the 16-valve Priora engine, you hear knocking noises in the engine compartment, which will disappear as the power plant warms up, then you should check the hydraulic compensators (HC). When every start of a cold engine is accompanied by a knocking sound, this is a clear sign of a worn hydraulic compensator. We will tell you how to replace expansion joints yourself. We will also look at a component such as the cylinder head check valve, which can also cause defects in the operation of compensators.

Hydraulic compensators are sensitive to the quality of lubricant. If mechanical impurities are present in the oil, the part may fail ahead of schedule. Faulty hydraulic compensators cannot be repaired. After installing new compensators, you may be upset by the knocking of the remaining main valves - this is normal, but not for a long time.

What's the result?

Taking into account the above information, we can conclude that there are many reasons for knocking hydraulic compensators. In some cases, it even happens that new hydraulic compensators are knocking. This happens when, in parallel, the engine oil was incorrectly selected, the oil filter is clogged, there are problems with the cleanliness of the lubrication system or the oil pump, or there are hidden or obvious engine problems that have not been eliminated.

Additionally, it is not recommended to immediately disassemble the internal combustion engine yourself for diagnostics, replacement or washing of hydraulic mounts without proper experience. The fact is that the cause of the knocking must be accurately established. There are quite common cases when, after washing and cleaning the hydraulic compensators, as well as the channels of the lubrication system, the knocking still remains. In such a situation, only professional engine diagnostics can help avoid possible consequences and unplanned financial costs.

Hydraulic compensators: what they are, what function they perform, hydraulic compensator malfunctions and symptoms. Do-it-yourself repair and washing of hydraulic compensators.

Valves knock on a cold engine or after warming up the engine: possible causes of valve mechanism knocking. Fault diagnosis, useful tips.

The most common causes of engine knocking are: piston knock, connecting rod knock, crankshaft knock. What to do if the engine suddenly starts knocking while driving.

Why a cold engine may knock: various malfunctions. Analysis of the nature of the knock in the power unit: ringing, metallic, muffled, etc.

What can knock, whistle, rustle and make other extraneous sounds under the hood after starting the engine. Diagnostics and determination of faults.

The appearance of knocking noises in different diesel operating modes. Fault diagnosis. The nature of the knocks of the crank mechanism, timing gear, and fuel equipment.

What to do if hydraulic lifters are knocking on LADA cars

Have you encountered any unusual engine noise? Perhaps it's the hydraulic compensators knocking. This problem occurs most often on Priora, but knocking also appears on other Lada cars (for example, Granta, Kalina, Largus Niva 4x4, Vesta or XRAY). Let's figure out why such a knock appears in the engine and how to deal with it.

The hydraulic compensator (also known as hydraulic pusher) is a cylindrical shape that is located between the camshaft and the valves. They perform two functions: transmitting force from the camshaft to the valves and eliminating gaps in their drive.

Diagram of operation of the hydraulic pusher in the valve mechanism of the VAZ-21126 engine: 1 – valve; 2 – check valve spring; 3 – check valve; 4 – cylinder head; 5 – camshaft cam; 6 – pusher; 7 – plunger; 8 – plunger spring; 9 – sleeve; 10 – check valve body; A, B – hydraulic pusher cavities; B – oil channel.

Is it possible to drive with knocking hydraulic lifters?

Many drivers are interested in the question of whether it is possible to drive with knocking hydraulic compensators and what consequences this can lead to. Let's answer it right away - it is possible, but it is not advisable, since the car will be plagued by a number of problems . In particular:

loss of power;
loss of control elasticity (the car will respond worse to steering);
unenvironmental friendliness (unhealthy exhaust plume from the rear);
excessive fuel consumption may occur;
increased vibration;
additional noise under the hood.

Accordingly, during the operation of a faulty engine there is a chance to “finish off” it completely. Therefore, it is strictly not recommended to drive with faulty engine components. After all, sooner or later it will fail. And the sooner you start repair work, the cheaper and easier it will cost you.

Lada Priora is equipped with a VAZ 21126 engine with an automatic gas distribution mechanism adjustment system. The gap between the camshaft cam and the valve stem is selected by a hydraulic tappet, the successful operation of which is ensured by the engine oil system. The mechanism allows you to avoid making various types of adjustments in the timing belt, reduces fuel consumption and increases the efficiency of the power plant. Fundamentals of the design and operation of a hydraulic compensator

Typical faults

Before examining the removed hydraulic compensator, you need to identify the non-functioning element. Compensators are located on the valves, so their number is equal to the number of valves provided on the engine. The check can be done without removing the camshaft. But first you need to understand why even new elements fail. There are 4 main faults.

The gap provided between the plunger itself and its bushing increases. As a result, oil will begin to leak. The compensator will not be able, so to speak, to select thermal gaps;
The valve does not close properly. This happens rarely, but it should not be ruled out. Because of this, the required pressure cannot be created between the plunger and the bushing;
Jamming of the plunger pair. The way the sleeve works is that it should move freely relative to the installed plunger. If this freedom is not there, hello jamming;
Blockages. Oil channels become dirty. Therefore, hydraulic compensators (HC) cannot work.

Compensator valve

It happens that this very valve does not hold oil. Then, when the engine is cold, it may leak due to loose connections. This is how air enters the system. When warmed up, it disappears ten minutes after starting.

To diagnose this, you need to start the engine. Let the engine run for at least three minutes. You need to keep the speed at 2500. Then reduce it to idle speed, and then add speed again. This is enough for the air to completely escape and the compensator to stop knocking. But every time you start, the hydraulic compensators knock again and again when cold.

Checking the cylinder head check valve

When disassembling the pusher, you will come across a cylinder head check valve, which contains a ball with a spring. Inspect the cylinder head check valve; if these elements are damaged, then only replacing the pusher will help. The cylinder head check valve along with its components can be replaced entirely, but these parts cannot be found in every car store. They are not in demand, as it rarely fails.

When you inspect the check valve, check whether it is dry or not. If the hydraulic compensator is working properly, then the check valve should be in oil. You can pour lubricant into it and see why the oil leaves.

Consequences

Incorrect operation of hydraulic pushers can lead to the following problems:

reduction in compression and engine power;
deterioration of its launch;
burnout of valve plates and seats;
an increase in shock load on vehicle components and parts, which will lead to their rapid failure;
increase in fuel consumption.

Knocking after replacement

Usually new parts don't knock.

If you still hear sounds, then this is a manufacturing defect or a problem with the valves. In order to perform an accurate diagnosis and make sure that there is nothing wrong with the valves, it is necessary to check their fastenings. There is a possibility that the parts did not shrink as required. We simply tighten them and thereby remove the knock of the hydraulic compensator.

How to find out which hydraulic compensator has failed

Acoustic diagnostics are usually sufficient. If this method does not help, then press the knot with a screwdriver. A normally functioning structure will compress if sufficient force is applied. If it is easily pressed through, then it is faulty and should be replaced as soon as possible.

In the second method, you should install the cams of the camshaft mechanism one by one with their protrusions facing upward. Here you need to make sure that there is a certain gap between the cam and the pusher. When pushing the compensator down, try to compare it with known-good parts. If there is a gap or the lowering speed is high, then you need to clean or replace the element.

AVTOVAZ diagnostic technique

Methodology for diagnosing and eliminating the defect “Knocking of hydraulic pushers”

Causes of knocking of hydraulic pushers

The main reason for timing knock is the valve seating at an unacceptably high speed, which occurs as a result of a violation of the kinematic connection between the valve and the camshaft cam. The main reasons for the disruption of the kinematic connection in the 16-valve engines of JSC AVTOVAZ are disturbances in the operation of the hydraulic pusher (hereinafter referred to as GT). Possible causes of such violations are given in order of likelihood of occurrence:

1. Gas content in oil is more than the maximum permissible 7%

a) Emptying of the lubrication system channels during long-term parking of the car due to oil leakage through the gaps in the plain bearings, leakage of the anti-drain valve in the cylinder head, leakage of the oil filter anti-drain valve. Before deciding to search for the causes, it is advisable to try to eliminate the knocking according to the “Recommendations for removing air from hydraulic pushers” given below.

b) Air leakage into the suction line of a leaking lubrication system through:

oil receiver sealing ring;
leaky welding seam of the oil receiver;
leaking oil pump cover casting,
leaky coupling of the oil pump housing with the cylinder block (for example, discrepancy between the design specification and the non-flatness of the oil pump housing).

c) Oil level does not meet the requirements of the engine design documentation:

if the level is excessive due to mechanical foaming of the oil by the crankshaft counterweights,
if the level is insufficient due to an unsettled top layer of oil entering the oil receiver.

d) The presence of water in the oil is above the maximum permissible norm (water turns into a gaseous state when heated).

e) Oil does not meet foaming requirements.

How to check hydraulic compensators yourself

You can check the condition of the spring.

You can also measure the size of the gaps between the guide bushing and the valve stem. If the gap is large, it must be eliminated.

Then you should turn the crankshaft so that the knocking valve begins to open. After this, you can turn the spring. The valve will turn with it. After starting the engine, the knocking noise should disappear completely. If the hydraulic compensators are still knocking when cold, the Priora needs to repeat the above operations. It is best to replace the damaged unit with a new one.

Determining the source of the knock

It happens that a knock comes from the engine compartment. Only the driver may not immediately understand what exactly is the reason and who is the source of this noise. You should not immediately blame the valves, since they are not the only ones capable of making knocks.

It is quite difficult for a novice motorist, in the absence of experience in operating and repairing a car, to immediately determine what kind of breakdown or malfunction provoked the occurrence of noises and knocks. Sounds uncharacteristic of a working engine can come from bearings, belts, crankshafts, and the valves themselves. Moreover, in the latter case, we hear a fairly clear and easily audible sound, accompanied by a metallic knock. And it comes from the gas distribution mechanism.

Another characteristic feature of valve knock is that it does not stop, depending on the speed. That is, the knocking will persist when the engine is running at low speeds, and also when the driver, by pressing the gas pedal, increases the engine speed.

An ordinary driver is unlikely to be able to simply tell by ear that a valve has failed.

But still, self-diagnosis is quite possible. To do this you need to do the following:

open the hood;
unscrew the plug through which engine oil is poured;
leave the engine running;
listen; listen
if the noise increases, the fault is in the valves;
or take a stethoscope;
apply the tool to the area where the noise is coming from;
listen; listen
draw appropriate conclusions.

This is just an approximate diagram of how to identify a breakdown and make a diagnosis practically in the field. Of course, it is often best to contact a car service center and undergo a comprehensive diagnosis. You can't joke with faulty valves.

As a consequence, you may encounter breakdown of the valves themselves, disruption of the timing belt, increased fuel and oil consumption, loss of power, and even failure of the engine itself.

The longer you ignore the problem, the more severe and expensive the consequences may end up being. If you hear a metallic knock while warming up or accelerating your car, go to a garage or service station. Don't delay diagnostics.