Why does the engine vibrate at idle and when driving?

Idle mode means that the engine is running in neutral. In this state, the torque from the engine is not transmitted through the gearbox to the drive wheels. At the same time, quite often drivers notice how engine vibrations noticeably increase at idle and are transmitted to the body. In its normal state, the engine practically does not vibrate, although minimal vibrations are allowed here, and they can be considered normal for a car. We must not forget that during the cold season, vibrations increase compared to engine operation in warm weather. When the engine warms up, the vibrations return to normal after a few minutes. If additional jerks, dips and omissions are not detected, everything is fine with the motor. The absence of extraneous noises and sounds is a pleasant signal for the motorist.

How to eliminate engine vibration at idle.

Primary diagnosis of causes

If the car's power plant is working properly, vibration is not felt during idling. When it appears, and it is also intense, transmitted to the body and felt even inside the car, it is worth conducting diagnostics to determine the cause of what is happening and correct its elimination. To do this, depress the clutch and listen.

If the vibrations continue, it means that the motor is really faulty, but if they stop, there may be problems in the operation of the gearbox and the clutch itself. Moreover, the type of gearbox, whether it is automatic or mechanical, does not play any role. In any case, it is necessary to urgently go to a service station and show the car to specialists, because professionals should be involved in repairing the power unit and putting the transmission in order.

By the way: you can check the condition of the gearbox yourself. To do this, you need to pour a small amount of oil into a container and examine its condition. The presence of metal shavings in lubricants, the presence of impurities and a burning smell indicate a serious gearbox malfunction. If the oil is normal, most likely the vibrations at idle are caused by clutch failure.

A common cause is also the incorrect operation of individual engine components. In this case, shaking is felt immediately after starting the engine and even when it stops. In such situations, experts recommend paying attention to the following:

• Engine airbag (it may be faulty).
• Condition of the fuel filter (clogging).
• Fuel pump clogged.
• Condition of the spark plugs (it is possible that they will have to be replaced).
• Components of the cylinder-piston group.

Ways to eliminate vibrations

After competent, professional installation of the causes of engine vibrations, they must be eliminated as soon as possible. The methods of “treatment” are very diverse, it all depends on the “diagnosis”.

Low compression

One of the reasons for engine tripping is low compression levels in the cylinders. This may occur due to the failure of any part that is part of the cylinder-piston group. In order to fix this problem, you will have to resort to disassembling the engine itself.

The cause of low compression may be a worn piston, piston rings and/or valves. In this case, the most optimal and rational option for eliminating vibration will be only a complete professional replacement of defective parts.

If you replace it yourself or restore it, further, more significant breakdowns may occur, and therefore costly repairs of the entire power plant.

Uneven air flow

If air enters the combustion chamber disproportionately, this can be corrected by simply replacing the air filter. You should also carefully inspect the air supply system for cracks and chips. It is recommended to replace the mass air supply and throttle sensors.

Incorrect fuel supply

In this case, professional car mechanics advise performing the following algorithm of actions:

• carefully inspect and clean the injectors;
• if after this the problem has not been resolved, then the injectors must be completely replaced;
• carry out an inspection of the condition and operation of the fuel pump, if necessary, replace the assembly;
• identify and reset ECU errors

Ignition system

When diagnosing early or, conversely, later ignition timing in the system, you should pay attention to the condition and soot of the spark plugs, as well as the integrity of the high-voltage wires. If replacement is required, it is best to do this with the entire set.

Engine mounts

If the fastening elements become loose or the engine mounts fail, it is necessary to strengthen the fastenings accordingly and consistently. Check the pillows for cracks and other defects; if necessary, replace them in pairs or completely.

In addition to the above measures, to eliminate strong vibrations emanating from the engine, proper installation of the timing belt, professional balancing of the crankshaft, as well as replacement of CPG elements of different weights (worn out) may be relevant.

Thus, the “dancing” of the power unit can occur for various reasons, which are also eliminated accordingly, each according to its own algorithm. Eliminating the causes of vibrations is a necessary process, since such vibrations, in addition to causing discomfort to the driver and passengers, can lead to expensive repairs of the car engine itself.

In addition, one of the common causes of strong vibration is the spontaneous loosening of fasteners. And if a major engine overhaul is an expensive procedure, but still fixable, then loose bolts and nuts, especially while the car is moving, can lead to irreparable consequences.

Balancing the cylinder-piston group and crankshaft

Often, during repair work on a power unit, it is necessary to grind the crankshaft or replace it. This leads to weight changes. It usually becomes higher than with the old part. So that after this the engine does not tremble at idle, balancing is performed - to balance the balance of the crankshaft with the clutch mechanism and the flywheel. This is done by drilling out parts of the part to reduce weight.

Vibration may be a consequence of installing new elements of the cylinder-piston assembly. Especially if they have a different weight compared to old components. To prevent weight changes from leading to increased shaking of the running engine, it is necessary to weigh the parts of the cylinder-piston system before assembling the power unit.

Why is it important to install the timing belt correctly?

If vibrations occur after replacing the timing belt, it is quite possible that it was installed incorrectly. Let us remember that this is a drive belt that transmits rotation from the crankshaft to the camshaft. Thanks to him, the gas distribution system, i.e. valve, works synchronously with the strokes of the piston system. If the belt is installed incorrectly, for example, there is a shift of at least one tooth, the valves begin to open and close at the wrong time.

This leads to dips in engine operation and tripping. Accordingly, at idle, as in the case of a faulty ignition, there is a strong vibration, which is clearly felt on the steering wheel and the entire body. The problem can be solved by correctly installing the belt. Therefore, it is advisable to replace it only in service centers.

Read more about why the engine vibrates at idle

The most common cause of engine vibration is, in fact, its tripling, that is, uneven operation of a group of cylinders. It is for this reason that the load on the crankshaft will likely be distributed unevenly, and the engine will begin to seem to move from side to side. Since the frequency of its operation is high, strong vibrations will begin to be felt. Vibrations are the first indicator that the engine is malfunctioning and needs to be checked urgently. Second indicator: steering wheel vibration. The third indicator: a noticeable drop in power, the appearance of dips when recharging.

A very well-known problem: improper mounting of the engine, resulting in vibrations. As a rule, we are talking about installing low-quality cushions that wear out quickly, or cushions and fasteners made of different materials. You can identify the problem in pairs: one person monitors the engine, and the other controls the operation of the unit from the cabin. Please note that there should be a slight deflection of the unit . If it “squints” in one direction especially strongly, then that’s where the pillow was badly worn.

A much rarer cause of vibration is the different mass of parts included in the cylinder-piston group. Surely every car enthusiast knows that engine parts must have not only a strictly defined shape, but also weight, or rather, the weight of a group of components must be the same. So, when selecting new pistons, you need to monitor their weight. If the difference is small, then, as a last resort, some of the metal can be removed from the non-working surface of the pistons - they will become lighter.

A very rare problem: improper operation of the fuel system and fuel contamination. Regarding the first: individual components of the fuel system may be contaminated, which ultimately affects the combustion of the fuel-air mixture. As for the second: the ingress of water into the fuel is guaranteed to provoke rapid coking of the cylinders, and only then the appearance of vibrations.

An even rarer reason: a large load on the generator. This is true for small cars where the throttle is controlled by an electronic throttle. As a rule, vibrations are observed during simultaneous operation of heated seats, mirrors, glass, as well as when the headlights and stove are working. Typically, the driver can feel engine vibrations after stopping the car.

Diagnostics

Checking the power plant is done in this way.

Fastenings

Check that all bolts are in place and that they are tightened. Sagging cushions and loose axles in 60% of cases provoke the transfer of vibration to the body, imbalance of the internal combustion engine.

Fuel system

Checking the fuel lines is necessary to eliminate air leaks. Leaked bubbles are the primary source of interruptions in the normal engine stroke. For example, on a VAZ 2110 the “sore” is located in the fastenings of the fine fuel filter. It is also necessary to diagnose the carburetor or injector. A grain of sand stuck in an injector or jet prevents the normal flow of gasoline and disrupts the operation of the installation.

Bad fuel

Low-quality fuel is a common cause of car jerking and instability of engine speed. This usually appears a short time after refueling. The problem can only be solved by draining the fuel and flushing the entire system.

Engine

The next common problem is wear or incorrect adjustment of the main components of the power plant. Clogged strokes, a worn piston group or broken bearings can cause more than just jerking of the machine.

The problem of feeding the engine with the fuel-air mixture

Also a common reason for visiting a service station. Problems in the fuel and air supply system guarantee an unstable supply of the mixture to the combustion chamber. The result is a jerking of the car, floating speed of the power plant.

The problem can be resolved by diagnosing all elements of the fuel line, replacing filters, and checking the functionality of the fuel pump.

Engine management system

The following problem is relevant for vehicles equipped with an ECM. Sensitive electronics often malfunction due to wetness, mechanical damage, system errors, or incorrect sensor readings.

The fault can only be eliminated through computer diagnostics.

Electrics

The most common category of diseases is found in the electrical circuits of the machine. Here the master is required to consistently study the entire structure, from spark plugs to the ignition coil. On the injector you need to look at the ECM and then the ECU.

It is also important to measure the fuel rail pressure for the injector.

Ignition system

The most common cause in the system is wear of spark plugs and high-voltage wires. The ignition coils or electronics may also malfunction.

Diagnostics must be performed from the final element (plug) and along the line to the fuses.

Incorrectly set car ignition

The ignition timing affects the ignition point of the fuel mixture. If the adjustment is made late or too early, the engine loses power, jerks or stalls. A secondary symptom is the appearance of detonation.

Gearbox failure

If the gears in the device are ground, this can cause them to slip, and as a result, shocks when driving.

This is also often accompanied by extraneous sounds, vibration, and possibly knocking out of gears.

Damage to the accelerator (gas pedal)

Hall sensors and PCV sensors may work intermittently, which gives a false signal to the ECU.

If the problem is in electronics, you need to perform computer diagnostics, where all errors will be revealed.

In the event of a mechanical breakdown, all parts are thoroughly washed, dirt is removed and the equipment is repaired. Usually the problem occurs due to contamination of the damper drive.

Transmission breakdowns

Transmission units often cause the car to jerk during acceleration. When the car reaches a stable speed, the trouble is felt less or disappears altogether.

If the breakdown lies here, it is accompanied by the howling of the gearbox, increased noise and the appearance of vibration.

Clogged air and fuel filters

A trivial problem can be fixed literally for pennies. If the filters have not been changed for a long time, their throughput is significantly reduced. In this case, the engine may choke, stall, or slowly gain momentum.

Clogged or faulty injectors

Stable problem on injectors. The defect occurs due to the use of cheap fuel of dubious origin, or wear of the filters. Thin injector channels are prone to blockages, which prevents normal injection of the fuel mixture.

An additional factor is wear or breakdown of the electromechanical part of the injector. The device driver or wiring may fail.

Mass air flow sensor or crankshaft position sensor

Mass air flow sensor and DPKV are in second place in popularity when contacting service stations. The mass air flow sensor is located in the intake manifold and sends data to the ECU. The second sensor monitors the position of the crankshaft.

If these elements malfunction or fail altogether, the engine will not work correctly, constantly jerking or failing.

General recommendations for finding the cause of car jerking

The machine itself will tell you where to look for the problem. If the malfunction is accompanied by a hum or grinding noise, the defect is looked for in the mechanics. If there are no extraneous sounds, the problem is located near the motor.

An additional assistant here is the dashboard display. The appearance of lamps and indicators on the device can quite accurately indicate the source of the breakdown.

Dual mass flywheel

Symptoms of damping flywheel failure:

• creaking, grinding noise when starting and stopping the power unit;
• rumbling sound when the engine is idling;
• vibration transmitted to the body and interior (with non-critical wear only in cold weather).

The reason for this behavior is the backlash of the elements of the spring-damper system, which is designed to dampen torsional vibrations. On cars with manual transmission, to check the flywheel, just squeeze the clutch. If the engine begins to run smoother and vibrations have decreased, it means that the reason for unstable idling is the dual-mass flywheel. The owner of a car with a robotic gearbox is left to rely on indirect signs and defects after disassembly.

Knocking and uneven operation when cold

Accelerated wear of cylinders and pistons is a real problem for many owners of Volkswagen and Skoda cars with gasoline engines. Recently, cases of scoring in cylinders on Hyundai cars have become more frequent. Due to the tendency to lighten the CPG elements, reduce the thickness of the piston rings, the flame zone and the length of the skirt, repositioning the pistons is associated with heavy loads. Local overheating associated with operating a car in traffic jams (disturbed air flow, long periods of idle time), improper engine warming up in winter, lead to wear of the CPG.

As a result, the engines begin to knock when cold. As it warms up, the knocking, and with it the increased vibration in the body, stops.

At a certain speed

If there is vibration in the car at high speed, the cause may be faults in the following components:

• transmission;
• steering system;
• suspension.

If vibration occurs in the body at a speed of 100–120 km, check the silent block on the suspension arms and ball joints. Failure of units is associated with driving on bad roads and frequent falling into potholes.

Wear of the shock absorber spring and strut support bearing leads to the car shaking when driving on uneven areas at speeds above 80 km per hour.

Wheel imbalance is the first cause of steering wheel shaking from 50 to 100 km/h. Driving at high speeds with such a malfunction is impossible and dangerous.

Wear of the steering tip will lead to the formation of large play in the unit, this will create an imbalance of the front wheels, leading to shaking of the car at speeds of 90 km/h.

We recommend: Is it possible to eliminate the hum in the power steering on your own?

If the vibration is caused by the transmission, it is easy to check. While driving, you should depress the clutch on a manual transmission; on an automatic transmission, set the handle to the “N” position. If the shaking stops, the problem is diagnosed in the gearbox unit.

Vibrations of a car diesel unit

If the car uses a diesel unit, its vibrations at idle can be explained by slightly different reasons. The reasons for this “symptom” will depend on the engine design, but usually they are:

1. The injection advance angle is incorrectly set;
2. There are malfunctions in the operation of diesel injectors, timing belt or high pressure pump;
3. There is a scattering of compression in the cylinders;
4. General malfunction of the cylinder-piston group or individual cylinders.

Unlike their gasoline “brothers,” diesel engines have normal idle speeds around 680-780 rpm. Most often, vibrations are caused by different compression in the cylinders, but after warming up and increasing the thermal clearances, the vibrations disappear. However, it is still worth measuring the compression.

A shift in valve timing observed after replacing the timing belt is guaranteed to lead to an imbalance in the operating cycle of the engine. This problem cannot be ignored, and it is not rare either. Otherwise, the reasons should be looked for in the same place as for a gasoline engine. True, problems associated with injectors and fuel pumps are observed much more often. Added to this is another cause of vibration: improper adjustment of the high-pressure pump.

Candles, “donut” and all the others: why vibration appears at idle

About the essence of the phenomenon

Today we will talk specifically about the vibration that appears at idle, for example, when stopping at traffic lights or in traffic jams.
And let’s also try to find the difference between the vibration of a cold and warm engine. But again: only the vibration that occurs when stopping or parking. It is logical to assume that the engine is to blame for the vibration (when stopped, nothing seems to be working in the transmission). This is almost correct, so let's start with the motor.

It doesn't spin much!

Indeed, the main cause of vibration is low idle speed. The nature of the vibration will be more or less uniform. Therefore, first you need to pay attention to the tachometer (or better yet, to a more accurate scanner) and find out whether the idle speed has dropped. Why they might drop is another topic, but if the idle speed is really below normal, you will have to do some diagnostics. Although on some cars the idle speed is naturally low, so it is difficult to deal with such vibration (for example, on a Honda Civic). So here we are dealing with a type of norm. Well, if the idle numbers really dropped, we need to deal with it.

Just don’t forget that idle speed can decrease significantly when many consumers are turned on (due to an increase in the load on the generator). And if during the first cold weather you suddenly notice that the car is shaking a little, try turning off the heated seats, windows, mirrors, steering wheel and whatever else is there. If after turning them off the vibration disappears, there is no need to worry - this is normal.

Another thing is uneven vibration, in which the car may also shake a little. Here, most likely, you will have to slip into banality - usually this is a sign of triplicity. Theoretically, the Check Engine light will also tell you about this, but not on all cars it lights up for any reason, so it can ignore isolated misfires. The solution is the same - diagnostics. Maybe it's time to change the spark plugs, maybe the injector is leaking or some sensor is acting up. In general, everything is clear about tripling - I won’t repeat it.

A more serious reason may be uneven engine operation due to reduced compression in one or more cylinders. Even if there are no malfunctions in the ignition system and there is still enough compression to ignite the air-fuel mixture, a significant difference in compression in one of the cylinders leads to an increase in vibration at idle. While driving, this may not be noticeable, and not everyone immediately feels the decrease in dynamics, but at idle the engine may already shake a little. Again, we go to the service center, measure the compression and draw conclusions. This is especially true for owners of diesel cars, the smooth operation of whose engines depends especially heavily on compression.

And, of course, don’t forget about the timing belt. Jumping the belt by one tooth does not always cause an error light on the panel, but it can shake well. Chain stretching also affects the vibration of the motor, so in these cases checking marks or phase synchronization with a scanner will not be superfluous.

All of the above are very common causes of vibration at idle. But, fortunately, in life the most common cause of such vibration is easier to solve and has almost nothing to do with the motor.

"I'm tired, I'm leaving"

On older cars, vibration of this kind almost always occurs for a simple reason - due to wear and tear on the engine mounts. As we all know, at least one of the engine mounts (or mounts) in a modern car is oil-based. The oil can escape from it due to a rupture or cracks, after which the engine “lies” on the body. The engine lying on the body jumps so that the vibration will be very noticeable. Therefore, first of all, you need to check the filled support.

Why, with a torn mount, can the engine shake the car not constantly, but only at idle? Usually for one simple reason: as soon as the engine begins to produce torque while driving, it tilts a little. And at this moment it moves away from the body. And when it stops, it falls back on the pillows (on their remains) and again begins to shake the whole car.

However, all simple rubber supports also lose their properties over time. Rubber hardens over the years and readily transfers vibrations to the body. And this is precisely what is most noticeable on a cold engine: if you stand in traffic jams, and even in the heat, the rubber parts become a little softer, and the vibration seems to decrease. And on a cold engine it appears again. The solution to the problem is simple - replacing the supports. Moreover, you will probably have to change all the supports at once, including the gearbox mounts (if there are any), because in this case the filthy sheep really spoils the whole herd and shakes the body even with all the other supports in good working order. Unfortunately, everything in this world ages over time, and wear and tear on the supports is inevitable. And it’s bad that analogues are usually noticeably worse than original pillows and either do not solve the problem or do not solve it for long. And original supports are often quite expensive.

A good way to check whether the mounts on a car with an automatic transmission are not damaged is to compare the vibration when the selector is in Park or Neutral and in D mode with the brake pressed. If the vibration is much more noticeable in “drive”, then almost one hundred percent the reason lies in the supports. True, there is one “but”: the box must be in good working order. Otherwise…

What if it's not the motor?

A more rare cause of vibration on a car with an automatic transmission is wear of the “donut” (torque converter). If he is about to “leave the chat,” then when he stops in “drive” and presses the brake, a vibration also appears. But, fortunately, this happens less often than wear of the liquid motor mount, and the bouquet of symptoms is richer. Here you usually encounter jerks during acceleration and straight-line movement, and a hum.

If everything has been checked a hundred times and of all the suspects, only the “donut” remains, it makes sense to start by changing the oil in the machine. Perhaps with fresh oil the situation will change for the better. In winter, you can check this circuit quite simply: immediately after starting the engine, turn on D and see if the engine is trying to stall when the brake is pressed. If it stalls, then instead of ATF there is some kind of impossible liquid in the box. It’s just a pity that this test requires a frost of 20 degrees, and it’s still a long wait.

Everything that spins

And finally, another reason for strange vibration is a malfunction of the mounted units and their drives. Of course, it will not be possible to detect vibration from a crooked generator pulley - this is not the case at all, and the symptoms will be different (it’s more likely that the belt will break than the car will shake). But sometimes it happens that something under the hood turns more difficult than it should. It could be a generator, a pump, an air conditioning compressor - anything.

It will not be the bearing that vibrates (this cannot be noticed), but the motor itself, which becomes difficult to operate at idle. This happens very rarely, but just in case, I’ll give an example from a friend’s service: the engine of one Ford Fusion did not show any errors, but was shaking like in a fever. The culprit turned out to be the pump. Moreover, usually when it wears out, it first simply flows and jams, but here it simply turned difficult and unevenly. And this was enough for the low-volume engine to have a dance on the pillows. I think this is a rare exception, but still, if you encounter this once, there is a chance that someone else may encounter this too.

What to be afraid of?

The vibration itself is, of course, unpleasant. It’s not for nothing that many automakers now install active engine mounts, which change operating parameters depending on the speed and load on the engine. You can forget about comfort with vibration, but this is not the most important thing. The main thing is that sometimes this vibration can warn of a more serious malfunction or prevent it. Take the same Fusion: if the owner had not shown concern in time, the pump would have jammed someday anyway, and the consequences could have been unpleasant. A timing belt jump or chain stretching also does not promise anything good, and engine tripping and an unexpected decrease in power can be downright dangerous.

In addition, the vibrations that are transmitted to the body do not in any way prolong the life of the wiring and connectors. Especially if this wiring is already old and dry. Fixation points, wiring in harnesses, bends and connections are frayed. And that's bad too. So you shouldn’t ignore the appearance of vibration - it definitely has a reason, and this reason must be sought and eliminated in any case.

How do engine oil additives help with engine vibration?

Motor oil directly affects the quality of operation of the cylinder-piston group and the entire combustion process of the air-fuel mixture in the cylinder. Lubricity, detergent properties, uniform distribution over the surface and stability of the oil film are all key factors for the normal trouble-free operation of all engine parts. Additives that improve these properties of motor oil prevent the formation of scuffs, scratches and other defects on the friction surfaces in the CPG, and therefore contribute to the uniform operation of the entire engine without jerking and vibration.

Are all additives useful?

Not all fuel additives are useful and have a beneficial effect on the engine. Some not entirely honest manufacturers, even world-famous ones, follow the path of a little deception when, with the help of an additive, motor oil does not improve its physical and chemical properties, but only thickens. This is done to prevent oil from penetrating into the combustion chamber through chips and scratches, as well as to improve the distribution of lubricant over parts and stabilize the oil film, which, due to the reduced fluidity of the oil, remains on the rubbing surfaces longer.

Not a single professional service station technician will advise you on a thickening additive for motor oil. This is a temporary solution to the problem and, rather, even disguises it. Overly thick lubricant will even harm the engine in the long run. Each automaker recommends motor oil with certain mechanical and physico-chemical properties, since the operation of the engine of each specific brand is designed for certain conditions of lubrication, washing and cooling of its cylinder-piston group.

Changing such conditions will lead to overload and overheating of the engine, poor lubrication of the elements of its CPG and the washing off of carbon deposits from them. All this will certainly lead to serious damage and expensive repairs, although at first car owners notice positive changes.

Problems with motor mounting

Another fairly common reason why the engine jerks at idle is its improper mounting (or a malfunction of one of the protective cushions). Usually, vibration in this case reverberates throughout the body.

It is quite simple to make sure that the problem lies here. True, for this you will need the help of a partner, who will alternately shift gears: neutral, reverse and forward. At this time, you need to open the hood and look at the engine deflection.

If the mount is installed correctly and the protective pads are not worn out, then the engine will tilt at the same angle each time. In this case, the supports themselves will be unloaded one by one. If the deviation in any direction greatly exceeds the norm, then the problem is in the mounting (the engine shakes). In this case, you will most likely have to replace the pillow.

Engine mounting

Strong vibration of the engine at idle speed can be caused by poor fastening of the power plant to the body. In some cases, it is possible to identify breakdowns of the protective cushion through which the motor is attached. It is advisable to carry out diagnostics together with an assistant, who will sequentially switch gears in the gearbox. An observer looking under the hood will identify which gears are causing problems.

Even after replacing the airbags, the shaking does not always leave the car. This is due to the need to properly configure and adjust the fasteners.

Failure can occur for any of the four supports (rear, front, bottom or top). However, practice shows that the most vulnerable is the front support. It is subject to increased static and dynamic load. As soon as one of the pillows breaks, then if no measures are taken, the rest will quickly break .

For novice drivers, vibration in the steering wheel at idle is not always obvious, so we recommend periodically undergoing diagnostics in specialized workshops or from experienced technicians. Otherwise, trouble cannot be avoided. If you decide to look for the cause yourself, then you need to use the method of exceptions, moving from simple to complex causes.

How to reduce engine vibrations

If the car has a carburetor, then to reduce vibrations this element requires careful adjustment, after which the idle speed is set. At the same time, the fuel pump is checked.

On injection cars, the fuel pump, injectors, electronic control system sensors, and fuel pressure regulator in the fuel rail are also checked. Additionally, it is recommended to clean the throttle valve and check the idle air valve, which supplies air bypassing the throttle valve at idle. Vibration of a diesel engine at idle may indicate certain malfunctions of the fuel injection pump or injectors, which will also require careful diagnosis and subsequent adjustment.

Disorders in the nutrition system

Ultimately, they come down to improper formation of the composition of the combustible mixture. Typically, vibration at idle is a consequence of its depletion. It is possible to understand exactly which node or element is the source of the problem only with the help of special equipment. There are many reasons, below are just a few of them:

• fuel pump failure;
• contamination of the filter and (or) fuel line;

• clogged jets in the carburetor or nozzles in the ramp;
• incorrect carburetor settings, faulty sensors in the injection engine, etc.

Speed

This is 800-1000 rpm. If the number of crankshaft revolutions is lower, the engine will begin to stall; with a higher number, fuel consumption will increase and engine parts will wear out faster. It is worth noting here that in the cold season, slight vibration after start is a normal phenomenon, which disappears after 5 minutes as the power plant warms up. If the engine shaking does not disappear, it is necessary to consider the reasons for its occurrence.

Other factors

In addition to a bad cylinder and an improperly mounted engine, vibration at idle can be caused by a number of other factors. Of course, they are much less common, but still they cannot but be considered as an option.

First of all, it is necessary to note the elements of the fuel system. If they are heavily contaminated, the fuel-air mixture will not burn sufficiently. This causes increased consumption, strange sounds (possibly even popping noises) and vibration. It's even worse if water gets into the gasoline. In this case, in addition to a large waste of fuel, there is a risk of coking of the cylinders. As a result, the engine does not work properly. Sometimes motor oil and soot can penetrate into the fuel system, which also negatively affects the operating cycles of the internal combustion engine.

The second reason is the different weight of the parts of the cylinder-piston group. Operating a car, especially if its mileage is more than 200 thousand kilometers, requires increased attention to the engine, and sometimes replacement of parts in it. Even a small difference in weight can have a significant impact on engine performance later on. Moreover, this applies to all engine parts, be it a piston, connecting rod or skirt.

On some small cars with an electronic throttle control system, interior vibration at idle may occur due to increased load on the generator. This happens especially often in the winter, when the car’s headlights, heater, and heated windows, seats, and mirrors are on at the same time. Often on such cars vibration occurs when stopping. When the driver releases the accelerator pedal, the on-board computer sends a signal to close the throttle to idle, and a load from the generator appears on the engine - it is at this moment that severe engine shaking occurs. As a rule, it disappears after 3-5 seconds. Such vibration at idle for small cars, especially with automatic transmission, is considered normal, and in most cases it can be solved by using higher quality fuel and replacing the air filter.

It is worth noting that engine shaking can also occur when replacing a timing belt, especially when the balancer shaft gear rotates along with the removed part.

When driving

If your vehicle experiences vibration at speed that increases as it accelerates and does not stop while driving, the problem may be wheel imbalance. In addition, shaking when driving is associated with a malfunction of suspension and electrical parts:

• shock absorbers, struts;
• support bearing;
• tie rod end;
• hinges;
• high-voltage wire break.

When a high-voltage wire breaks, the car begins to vibrate when driving and a characteristic crackling sound is heard. Finding the location of the breakdown is quite simple; a spark is noticeable when the engine is running and idling. But if the electrical wiring is in order, but the appearance of extraneous sounds under the hood is noticeable, you should check the electronic sensors.

Wheels are out of balance

Vibrations caused by the wheels are usually felt through the steering wheel. One possible culprit for this could be a worn or damaged wheel bearing. Although they should last quite a long time, as with any other mechanical part of the car, they can fail at any time.

Another thing to look for is rod ends or ball joints. If the steering wheel feels normal while you're driving straight, but starts to shake when turning, this could indicate worn rod ends. However, if the steering wheel shakes in a straight line but stops when you turn, this may be a sign that the ball joint is faulty and should be replaced.

Vibration can be another cause of vibration and shaking in your vehicle. The term refers to any deviation from a truly circular rotation and is measured by a special indicator.

Best driving instructors:

Driving instructor Svetlana Teaches in the Northern Administrative Okrug, North-Western Administrative Okrug, Khimki Driving instructor Elena Teaches in the Southern Administrative Okrug, South-Eastern Administrative District, Vidnoye, Domodedovo Driving instructor Marina Teaches in the Northern Administrative Okrug, Dolgoprudny Driving instructor Irina Teaches in the North-Western Administrative Okrug, ZAO Automotive instructor Natalya Teaches in the Eastern Administrative Okrug, Balashikha, Reutov Driving instructor Oleg Teaches in the Northern Administrative Okrug, Dolgo pond Driving instructor Yana Teaches in the Northern Administrative Okrug, Dolgoprudny Driving instructor Yulia Teaches in the Eastern Administrative Okrug, South-Eastern Administrative Okrug, Lyubertsy, Reutov, Zheleznodorozhny Driving instructor Svetlana Teaches in the North-West Administrative Okrug Automotive instructor Tatyana Teaches in Krasnogorsk Driving instructor Peter Teaches in the North-West Administrative Okrug Automotive instructor Oksana Teaches in the North-East Administrative Okrug, Mytishchi, Korolev, Pushki not Automotive instructor Dmitry Teaches in North-East Administrative District, Northern Administrative District, North-Western Administrative District, Dolgoprudny Driving instructor Oksana Teaches in the Southern Administrative District, South-Western Administrative District, Vidnoye, Podolsk Driving instructor Dmitry Teaches in the Southern Eastern Administrative District, Lyubertsy

How to determine the cause of vibration and eliminate it?

The first step is to determine the root cause of vibration and then boldly eliminate it.

• Check the fuel system and spark plug operation.
• If the engine has recently been repaired and disassembled, check the quality of its fastening at a service station.
• Make sure the support pads are in good condition.
• The runout of an unbalanced crankshaft can be either an independent cause of vibration or a consequence of malfunctions in the CPG.

Troubleshooting is the most common cause of vibration in an engine at idle. This malfunction can be detected at a service station. However, you can notice the signs of tripling yourself.

• More frequent misfires.
• Frequent popping sounds from the exhaust pipe.
• Significant reduction in engine power.
• Vibrations from the engine compartment at idle, transmitted to the steering wheel.
• Darkening of the spark plug in an idle cylinder.
• Long acceleration times and jerks when accelerating.
• Increased fuel consumption.

It is necessary to eliminate such a malfunction as quickly as possible, since this exponentially leads to aggravation of the problem, further breaking the pistons, cylinder cups and crankshaft. During triplication, unburned fuel washes away the lubricant in the engine cylinders, increasing the coefficient of friction and accelerating wear of the rubbing surfaces of the cylinder-piston group.

Causes of engine vibrations in different operating modes

Vibration can be observed both constantly, regardless of engine speed and warming up, and during certain operating modes - at idle, when starting cold or hot, at low or high speeds while driving.

Low speeds during idling of the internal combustion engine often lead to slight vibration of the entire car, including the steering wheel. While there is no clutch and the engine does not transmit power to the wheels, it operates at a minimum speed of 800-1000 rpm. If the tachometer shows lower or higher values, this is already a reason to contact a service station, but this is also an average indicator, which may differ in both directions depending on the make and model of the car.

Resonance often occurs when the engine is started cold, and when it reaches normal speed, the vibration goes away after warming up for 3-5 minutes. If the engine continues to vibrate at idle after starting or while driving, i.e. when hot, and the vibrations themselves become more and more noticeable, this already indicates a malfunction. Among them, car service experts identify five main ones:

• Incorrect motor mounting. This problem often occurs when the car is repaired unprofessionally and the engine is disassembled. Lack of balancing and improper mounting can all lead to vibrations when starting cold or hot, when idling and while the vehicle is moving.
• Faulty engine mounts. This problem can arise by itself under extreme operating conditions of the car or be a consequence of the previous point - improper disassembly and reassembly of the engine, violation of the car repair technology, etc. With this type of malfunction, a cold engine vibrates especially noticeably. This is due to the fact that the polymer elements of the motor mounts lose their elasticity when cooled and do not fully perform their damping functions. After the engine warms up, the vibration stops due to the restoration of the shock-absorbing properties of the gaskets.
• Unbalanced crankshaft. A loose crankshaft leads to pendulum oscillations of the engine, which resonates with the small vibrations of the car, creating a powerful vibration that is noticeable in the cabin. Vibration with an unbalanced crankshaft can be observed both at idle when starting cold or hot, and while the car is moving.
• Vibrations when starting the engine when cold can also be observed with faulty fuel injectors. Simply put, an insufficient amount of fuel enters the combustion chamber, which prevents the combustion of the air-fuel mixture and leads to triple combustion.
• Engine tripping. This is the most common reason for engine vibration at idle. In addition to malfunctions in the fuel system, problems in the cylinder-piston group itself often lead to tripping, incl. wear of its elements and friction surfaces. Uneven operation of the cylinders introduces the engine into vibration resonance precisely at low idle speeds. While driving, when the engine is running under load, this effect is not so noticeable.

Jerking and jerking of the engine, leading to general vibration of the machine, appears as a result of uneven distribution of the load on the crankshaft. Even if you press the gas pedal at idle, thereby compensating for the drop in power and speed due to an inactive cylinder, the driver will still feel a noticeable vibration. It is transmitted to the steering wheel, through which drivers most often detect suspicious rattling, and it can also be transmitted to the hood, which literally begins to drum.

• Engine oil additive "Suprotek Active Plus"

  Restores compression, reduces fuel consumption and oil waste, reduces wear rate and extends the life of internal combustion engines of any type. Facilitates cold starts and protects against overheating in traffic jams.

  more reviews

Saving engine life

Remember: low speeds are more dangerous to a car engine than high speeds. Reducing the idle speed will lead to unstable operation of the unit and a rapid reduction in engine life .

If you are the owner of a car with a gasoline engine, try not to allow a further decrease in the speed already at around 2000 rpm. If the engine “does not pull”, for example, when trying to drive on hills, it is enough to switch to a lower gear. The appearance of vibrations is a very bad signal.

Also, do not forget that the service life of the engine and its adjacent components can be affected by seemingly unimportant details. For example, internal combustion engine airbags . Often they try to save money on replacing them by purchasing inexpensive analogues from Asian companies. Good and relatively inexpensive options can be found under the brand names Impergom, Boge, Lemfoerder, Ruville, Hans Pries (pay attention to the article number - the last symbols indicate the quality standard of the product). The same can be said about the choice of sensors, timing belts and fuel pumps - you should not skimp on them.

What are the consequences of low idle speed?

Driving and operating the engine at excessively low speeds, especially when attempting to accelerate, can cause rapid wear on the following components:

• Engine pistons (this destroys the cylinder block).
• Crankshaft liners.
• Clutch baskets.
• Flywheel.
• Transmission bearings.
• Timing chains. At low shaft speeds it simply stretches.
• Cylinder liners. Due to soot, their walls are damaged.

Thus, with constant vibrations, rapid wear of engine parts occurs. At the same time, its rotation is much slower, and the crankshaft packing is greatly destroyed. As a result, there is a risk of oil leakage.

Reasons why the engine vibrates

The answers to the question of why the engine vibrates at idle may vary. There are several reasons for this unpleasant phenomenon:

• "triple" of the engine;
• violation of the fastening of the power unit;
• crankshaft imbalance.

Engine trouble occurs as a result of improper functioning of the cylinders - they begin to work unevenly. The vibration is felt most strongly at idle, and after pressing the accelerator pedal it is possible to somewhat compensate for the imbalance due to the fact that the crankshaft begins to rotate more often, but the engine power will still be noticeably lower.

Signs of tripling include the following:

• Weak acceleration, resulting in jerking.
• Increased fuel consumption.
• Noticeable vibrations in the steering wheel.
• When turning the key, gaps occur in the ignition switch.
• One of the spark plugs turns black.
• The appearance of pops from the exhaust system.

If tripping and vibration are associated with cylinder failure, the malfunction must be eliminated as quickly as possible, because the fuel will not be compressed enough, and its excess will lead to the washing of the lubricant from the cylinder walls and to its premature wear.

Also, because of this, unburnt fuel will penetrate through the seals into the oil, and it, in turn, will lose its performance characteristics, which can lead to even more serious breakdowns and the need for large-scale repairs.

When excessive engine shaking is caused by crankshaft imbalance, this means that its speed has become higher or lower than normal, which averages 750-950 rpm. (depending on the type of power plant). If the speed is lower, the engine functions unstable and begins to stall.

If, on the contrary, there are too many of them, gasoline or diesel consumption increases, the load on the parts of the cylinder-piston group increases, and this leads to a significant reduction in engine life.

Therefore, experts advise studying the instructions for the car, finding out the optimal crankshaft balance and strictly adhering to it, and if the required indicators are violated, immediately go to a service station and perform balancing.

What you can check and fix yourself

As mentioned above, the easiest way is to check the integrity of the engine mounts; we wrote about how to do this at the very beginning of our material. You should also do a visual inspection of the spark plugs, coil and wires.

If darkening, insulation damage or other defects are found on them, it is necessary to urgently replace the suspicious part. Usually after this the idle speed returns to normal and the shaking disappears.

What else could cause this phenomenon?

If, after examining the operation of the fuel supply channels, ignition system, support cushions and understanding that all this is functioning normally, the engine continues to vibrate in neutral speed mode, then the reason is something else.

One possible option is a faulty gearbox. To determine the source of the problem, fully depress the clutch pedal. If the jerking goes away, the vibration is caused by the clutch or transmission.

Note! Similar problems can arise when a “mechanics” or “automatic”, as well as a variator or “robot” breaks down.

Incorrect operation of some on-board computer sensors responsible for controlling the power unit can also cause shaking in idle mode. Check the operation of the sensors:

• mass air flow;
• crankshaft position;
• Hall;
• idle speed.

Another option is familiar to owners of cars with small engines. If powerful consumers (climate control system, heated seats) are turned on in such vehicles while idling, the engine may experience increased vibrations. They disappear as soon as the driver presses the gas pedal. The same effect can occur if the generator is damaged.

Vibrations in diesel engines

In addition to the main factors, increased vibrations at idle in diesel units are caused by malfunctions in other parts of the vehicle structure. The stable operation of these internal combustion engines strongly depends on the condition of the parts and components of the fuel supply system, for example, on the degree of their contamination. Contamination occurs due to particles and impurities (including water) from the fuel and air entering the fuel system components due to poor filtration.

The culprit for increased oscillations may be a malfunction of the fuel supply system components and, first of all, the injection pump.

If vibration is felt the first time after starting a cold engine, but disappears after warming up, then the glow plug is faulty. In addition, the serviceability of the engine should not be excluded from the list of reasons - the presence of a compression level that meets the standards.

Triple

So, the first reason that provokes engine vibrations. Engine tripping is the most likely cause of unstable operation of the internal combustion engine, since when the cylinder is not working, a significant imbalance and improper distribution of the load on the crankshaft occurs. As a result, you can see the motor jerking from side to side. Also, when driving, vibration of the steering wheel is noticeably felt. At idle speed all these signs are more noticeable. The more the shaft rotates, the less strange vibration will be noticeable. But at the same time, you will notice how the car begins to absorb more fuel and noticeably lose power, especially when driving downhill.

Vibration when driving under load

There is another type of vibration - under load.

The appearance of vibrations while driving not at idle speed of the engine, but under load, always indicates problems in the operation of the engine. The occurrence of such an unpleasant phenomenon is preceded by various reasons.

Chassis imbalance

If the wheels are not balanced correctly, this becomes evident when driving at speeds of 70 km/h and above. Moreover, the force of shaking can be so noticeable that it is transmitted and felt even on the steering wheel. The problem can be solved extremely simply - by visiting a service station and balancing the wheels.

The procedure is accessible and does not take much time. It is important to note that imbalance often occurs in winter, in bad weather, when wet snow sticks to the disks, but vibrations in this case are more noticeable than on poorly balanced wheels.

Fuel system clogged

Problems that lead to engine shaking also occur due to malfunctions in the fuel system, in particular due to its clogging. They consist of problems with the fuel supply, which is why the fuel mixture is formed incorrectly. Vibrations are usually noticeable if the mixture in the cylinders is lean.

Carrying out accurate diagnostics in the current situation is possible only with the use of special equipment, and we are talking about the diagnostics of both carburetor and injection internal combustion engines. Often the problem is a faulty fuel pump or clogged fuel filters.

And also in clogged fuel injectors, unadjusted carburetor. Typically, diagnostics of the fuel supply system are performed after it has been verified that the ignition is working properly, and also that the cause of the vibration is not a broken engine mount.

Sensor malfunctions

Engine malfunctions often result from failure of the sensors that send signals to the engine ECU. For example, if the lambda probe, idle speed control, speed indicator, etc. are faulty, the control unit operates in emergency mode, which is why there is a high risk of disturbances in the formation of the fuel mixture and the resulting unpleasant consequences.

The same thing will happen if the crankshaft position sensor, phase sensor, etc. break down. You can find out what exactly requires replacement only by performing computer diagnostics, as well as deciphering the error detected by the electronic controller.

Tips and tricks

As you can see, to prevent vibrations, regardless of whether the engine is carburetor or injection, it is necessary to maintain the cleanliness of the fuel system, the functionality of the ignition system, etc.

The fuel pump and ECM sensors, fuel and air filters deserve special attention; the fuel injectors, idle air valve, and accelerator pedal need to be adjusted. It is important to understand that vibrations that are not eliminated in a timely manner lead to the following negative consequences:

• cracks in the car body;
• gradual unscrewing of even the most tightly tightened nuts and bolts (which can lead to an emergency);
• premature wear of parts, resulting in, for example, oil leakage, destruction of bearings, seats, fasteners, etc.

We also note that sometimes motorists are faced with a problem such as a drop in speed to 500 rpm. on a warm engine at a rate of 750-900 rpm. As a result, the internal combustion engine begins to vibrate strongly. This indicates problems with the throttle and sensors (for example, TPS).

Also, drivers often deliberately lower idle speed to save fuel (especially if they have LPG). At the same time, the consequences of engine vibrations will subsequently lead to repairs, which in cost will cover all the savings on fuel.

We also recommend reading the article about why a diesel engine vibrates at idle. From this article you will learn about the causes of diesel engine vibration at idle, as well as ways to identify and eliminate the problem.

Even while driving, it is important to consider at what speed to drive. The fact is that if the car is used incorrectly, vibrations can also occur. To prevent this from happening, you should adhere to the following rules:

• upshifting must be done between peak torque and peak power;
• when vibration occurs, it is necessary to switch to a lower gear to avoid engine damage;
• if the car does not pull, you must also switch to a lower gear, but do not allow vibrations to occur.

This approach will avoid premature wear of parts, while ignoring it will quickly damage engine pistons, transmission bearings, clutch basket, crankshaft liners, etc. Carbon deposits and wear appear on the walls of the cylinder liners; due to constant vibration, oil seals begin to leak, and shafts begin to run out.

Why is engine vibration dangerous at idle?

As mentioned above, if the problem that has arisen is not corrected in time, it can cause other problems. Sometimes even more serious.

Vibration causes the greatest damage to the car body. First, the plastic elements of the interior suffer, then the fastenings of the parts become loose. Due to prolonged shaking, the paintwork may also come off (as a result of which the metal also begins to suffer from corrosion).

The engine itself is also damaged: strong vibration causes its parts to wear out much faster, and the crankshaft packing is destroyed (this causes oil leaks). As a result, the speed does not reach the required values, the acceleration is much slower, and the power is reduced.

Therefore, when eliminating the causes of vibration, it is necessary to check the parts that could be damaged due to it (particular attention should be paid to the fasteners) and, if necessary, repair or replace them.

The engine jerks at low speeds: procedure

1. First of all, you should check the operation of the spark plugs. They should give a good spark and not have a large amount of carbon deposits on the surface.
2. Next, you should inspect the engine compartment. If everything is in order, the engine will deflect at the same angle when changing gears.
3. The next thing that is important to pay attention to is the cleanliness of the fuel system. This is especially true for filters. If necessary, they should be replaced.
4. If the injection engine jerks at low speeds, updating the software and cleaning the injectors can help. This is also worth paying attention to.
5. If all of the above did not help, the reason may lie in a change in the weight distribution of the CPG or an uncalibrated crankshaft. In this case, it is better to turn to professionals. Correcting the situation will require complex and expensive equipment, and the intervention of an untrained person can only further damage the car.

Danger of vibrations

The causes of vibrations that occur must be eliminated as soon as possible after the first signs of problems occur. This is explained by the fact that after vibrations, other problems often develop that can cause enormous damage to your vehicle. As experts themselves note, the greatest damage due to vibrations is caused to the car body. The first to wear out and break are the plastic elements, then gradually all sorts of fastenings, located sometimes in very hard-to-reach places, become loose. When the car shakes for a long time, the paint layer may begin to deteriorate. This already entails the formation of corrosion and the spread of rust throughout the body.

We must not forget about the harm that is caused to the power unit. The engine also suffers significantly from unnecessary vibrations. Vibration causes accelerated wear of parts, destroys the packing in the crankshaft, and then oil begins to leak. As a result, the engine cannot produce the required number of revolutions, the car accelerates more slowly, and fuel consumption increases significantly. And at the same time, engine power decreases, which negatively affects control. If you noticed that the car began to vibrate, but were able to find the reasons and eliminate them, the work is not yet completed. In addition to this, be sure to check all the parts that could have been damaged in any way as a result of the vibrations that have arisen. You can eliminate the source of vibration, but you cannot exclude the fact that some destructive processes have already been launched. The fastener has come loose, the paintwork has been damaged, and therefore new problems will potentially arise soon.