The car starts to warm up and idles steadily but feels a slight shaking under your feet, what is the

Main causes of idle jitter:

1.Serious engine carbon deposits: Cars always have the problem of carbon deposits, including cylinder carbon deposits, throttle carbon deposits, spark plug carbon deposits, intake carbon deposits, etc.

When the engine has too much carbon deposit, it will affect the ignition energy, air intake efficiency and air-fuel ratio of the car, resulting in the unstable power output of the car, and the phenomenon of idle speed and acceleration jitter appears.

2.Unstable oil pressure: If you have cleaned the engine carbon deposits, cleaned the throttle, replaced the oil gasket and spark plug, etc.

And when idling, you still find that the body shakes, it is recommended that you go to the 4S shop to check whether the oil supply pressure and intake pressure sensor are normal, if the oil pump supply pressure is abnormal, or the intake pressure sensor value is wrong, and the work is not good, it will cause the body to shake.

3.Engine cylinder shortage: Engine cylinder deficiency mainly refers to the engine one or more cylinders are not working properly, which is generally manifested as:

The exhaust fumes coming out of the car are obviously intermittent, and the exhaust pipe shakes violently, and the engine shake can be clearly felt, sometimes accompanied by abnormal noises. This is mostly related to ignition coil failure.

4.Aging of engine parts: Shake in the car is also associated with the aging of the engine feet (also known as claw pads).

The engine foot is actually the shock absorber system of the engine. The engine feet are responsible for absorbing slight vibrations when the engine is running. If there is a problem with the engine base, these vibrations can be transmitted to the steering wheel and cab, causing vibrations at idle.

Solution; The best way is to clean the oil circuit, clean it regularly, and use PNF fuel additives to solve the above problems caused by carbon deposits. The fuel quality is not very good or the initial fuel of the new car is stored for too long, resulting in a rapid increase in the colloidal composition of the oil circuit, which will continue to pollute the fresh fuel and cause no good fuel to participate in combustion in the later stage, and the carbon deposition exceeds the standard, which is especially common for China VI vehicles. We can only gradually alleviate most of the problems by maintaining clean oil circuits.

The reason for the lack of cylinders in cold cars and hot cars is that the valves of the car are not tightly sealed.

The solution is: if the valve of the car is not strict, you need to go to the 4S shop or repair shop of the car in time to overhaul the valve device of the car, which can solve the problem of the car's hot car lack of cylinder.

It was found that the engine was working abnormally or the power was insufficient, and the engine worked unevenly at high, medium and low speeds, and the rhythmic vibrating muffler discharged black smoke and fired the gun. The lack of cylinder in the engine can lead to large fuel consumption, black smoke, weakness, horsepower decline, and the vehicle hall can not increase the speed, serious shaking, and increased driving noise.

Extended data with voltaic roll:

The introduction of the lack of cylinders in the hot car is as follows:

It is very detrimental to driving safety. Especially on the road section that needs to be sloped, the engine load of the vehicle with a lack of cylinder increases, the body shake is more obvious, and it is very easy to have an instantaneous dead fire. The lack of cylinders in the cool car due to the failure of the ignition system may be caused by the excessive clearance of the spark plug.

The spark plug gap refers to the gap between the center electrode and the side electrode of the spark plug, and the spark plug gap affects the fuel combustion time and the degree of combustion.

This should be the tremor caused by the engine driving the body resonance, which is normal, every car has resonance, but the performance is obviously not obvious.

1. Excessive carbon deposition or aging of the engine.

If there is too much carbon inside the engine, the gasoline sprayed at the cold start injection head will be absorbed by the carbon deposit, resulting in the cold start mixture being too thin, making it difficult to start. After the car hits the car, the gasoline adsorbed on the carbon deposit will be sucked into the cylinder by the vacuum suction of the engine for combustion, and the mixture will become thicker, and the combustible mixture of the engine will be dilute and thick, resulting in idle shaking after cold start.

2. The engine foot is aging.

The engine foot is actually the suspension system of the engine, and the engine foot is responsible for absorbing the subtle shake of the engine when it is running, and if there is a problem with the engine foot, these vibrations will be transmitted to the steering wheel and cab, causing shaking when idling.

3. The oil pressure is unstable.

If the oil pump supply pressure is not normal, or if the intake pressure sensor is wrong and does not work well, the body will shake. The solution is to check the oil pressure and replace the parts if necessary.

The car has just started cold, the idle speed is unstable, the engine shakes, it may be the engine valve and intake tract carbon deposition caused by the shake, or it may be the water temperature sensor, the air flow device is dirty, the specific analysis of the reason, it is recommended to send it to a professional 4S shop for inspection and maintenance.

Leakage from the intake manifold or various valves.

When the air that should not enter, gasoline vapor, and combustion exhaust gas enter the intake manifold, the mixture is too thick or too thin, and the engine burns abnormally. When the leakage position only affects individual cylinders, the engine will shake more violently, which will have a greater impact on the idle speed of the cold car. Common causes are:

loose intake manifold clamp or cracked hose; The intake manifold gasket is leaking.

Damage to the intake manifold or other parts to grind out of the intake manifold; Injector O-ring leakage; The plug of the vacuum tube falls off and cracks; The crankcase forced ventilation (PCV) valve has a large opening; The activated carbon tank valve is normally open; Exhaust gas recirculation (EGR) valve is not closed tightly, etc.

Engine idling is unstable, which can lead to many reasons, the common ones are as follows: 1. Lack of cylinder, check the spark plug, fuel injector, and cylinder tightness. 2. Idle speed control failure, need to be cleaned. 3. Ignition system failure, spark plug, high voltage line, ignition coil failure.

4. If the electronic control system fails, the water temperature sensor, the oxygen sensor, the air flow sensor, etc., the fault code is retrieved by the diagnostic instrument. 5. Air intake system failure, air leakage, etc. The specific reasons need to be listed one by one.

The main reasons for the shaking of the car engine are as follows:

1. If it is shaking or passing when you are in the car.

After two or three minutes, it was slightly better, or better, that is, the rubber bracket in the "machine grip" that fixed the engine was broken; It needs to be replaced;

3. If it shakes after getting into the car, it will still be after refueling; Key inspections: individual cylinder working status, oil supply, fuel injector, spark plug, high-voltage line, ignition coil, oil pump working condition, timing belt, various conveyor belts related to the engine;

In addition, in terms of maintenance, it is important to check the carbon deposits of the throttle.

Causes of unstable car idling.

1. Air leakage from the intake manifold.

When the air that should not be entered, gasoline vapor, and combustion exhaust gas enter the intake manifold, the mixture is too thick or too thin, causing the car to idle unsteadily.

2. Too much carbon deposition on the throttle.

Excessive carbon deposition in the throttle valve and surrounding air intakes, and changes in the cross-sectional area of the air channel, make it impossible for the control unit to accurately control the amount of air intake at idle, which will also lead to too thick or too thin mixture, resulting in unstable idling of the car.

3. Failure of the actuator of the air intake system.

There are many actuators in the engine intake system, such as throttle motors, idle stepper motors, duty cycle solenoid valves, air flow meters, intake pressure sensors, etc., which cause the car to idle unstable.

4. Fuel system failure.

Faults such as clogged injectors, clogged fuel filters, clogged fuel pump filters, faulty fuel pressure regulators, and clogged return pipes can all lead to incorrect fuel injection, resulting in over-concentrated or over-thin mixtures, resulting in unstable car idling.

5. Ignition system failure.

Faults such as ignition module failure, incorrect spark plug clearance, spark plug electrode ablation or damage, and excessive resistance of the high-voltage line lead to a decrease in ignition spark energy or misfire, resulting in unstable idling of the car.

Hello! If the jitter is severe and the rotational speed varies greatly, it is recommended to check the oxygen sensor. Car jitter is also associated with aging of the engine feet.

The engine foot is actually the suspension system of the engine, and the engine foot is responsible for absorbing the subtle shaking of the engine when it is running, and if there is a problem with the engine foot, these vibrations will be transmitted to the steering wheel and cab, causing shaking.

If the car is hot and idling and shaking, it is recommended to clean up the carbon deposits in the engine, which should be better, and you can refer to it.

All Lavida cars have jitter at idle, and there is no reason for this.

A car of 300,000 is much smaller than a car of 100,000 yuan, which is related to **, and it is also a matter of grade. This is the case for all cars.

This can happen due to severe carbon deposition in the engine, ignition system problems, unstable oil pressure, aging engine components, dirty throttle valves, excessive carbon deposition in fuel injectors, etc.

1.Excessive carbon deposits in the engine:

When there is too much carbon inside the engine, the gasoline sprayed by the fuel injector of the starting vehicle will be absorbed by a large amount of carbon deposits, resulting in too thin mixture, resulting in difficulty in starting, and the vehicle will only be easy to start when the gasoline absorbed by carbon deposits reaches a saturated state. After the engine starts, the gasoline attached to the carbon deposit will be sucked into the cylinder by the vacuum suction of the engine and burned, so that the mixed gas becomes thicker. When the combustion mixture of the engine is thick and sometimes thin, it will cause idle jitter when starting.

On the other hand, when the engine starts, the speed is relatively low, and the fuel injector sprays more gasoline than the vehicle during driving, and the more gasoline is sprayed, the more energy the engine produces, and the more power it has. According to the formula: power = force speed, in the case of the same power, the speed is low, and the force increases.

This force strikes the engine's cylinders, causing the engine to shake significantly when it starts.

2.Air Filter:

If the air filter is not replaced in time, it will cause insufficient air intake, and the engine idle speed will be reduced, which will cause the engine to shake.

3.Low ignition energy:

When the vehicle starts cold, the internal temperature of the engine is not enough, and the fuel injector sprays more gasoline to meet the power requirements during the cold start. Fuel requires higher ignition energy, and a larger gap between the spark plugs will lead to a decrease in ignition energy, which in turn will affect the dynamics and cause the vehicle to shake.

4.The water temperature is not normal:

When the water temperature of the engine is high, the ignition time becomes earlier, the oil-air mixing ratio changes, and the viscosity of the oil becomes thinner (lubricity becomes worse). The causes of abnormal water temperature are: lack of coolant, thermostat cannot be opened, fan failure, and inaccurate temperature of the temperature control switch.

Analysis of the causes of car shake:

1. Cold start jitter.

First of all, starting from the cold start, the main reason for the cold start body shaking is that the fuel combustion is insufficient, resulting in insufficient power of the car. The ignition energy is low, and when starting, especially when the temperature of the fuel and lubricating oil is low, more oil is required to meet the power. Over time, the pole gap of the spark plug gradually increases, resulting in a decrease in ignition energy and poor fuel atomization, which leads to the shaking of the body.

In addition, the ignition energy can also be reduced due to the aging of the ignition coil, the aging of the high-voltage wire of the spark plug, or the leakage of electricity.

2. Suspension system problems.

Body shake is also related to the aging of the suspension system. It is mainly responsible for filtering out the shake of the engine when it is running, and if there is a problem with the suspension, these vibrations will be transmitted directly to the steering wheel and cab, affecting the driving. When the engine is idling, it is easy to cause shaking when the electrical system in the car is turned on.

The engine will increase the load when the electrical appliances are turned on, causing the idle speed to drop, and to compensate for the jitter caused by the idle slip, the engine will automatically increase the speed by partially. So, when the electrical system, especially the air conditioner, is turned on, the engine will often shake. This jitter is likely to be caused by the aging of the shock absorber and needs to be replaced in time.

3. Tire problems.

For tires, the tire must be balanced once when the car is replaced with new tires and new steel rims, otherwise the steering wheel will be prone to shake when the counterweight is uneven. If you find that the tire weight is not equal, you need to add lead to the inside of the rim to average the weight of the tires on both sides. Whether it is a general steel ring or a lightweight aluminum ring, it may deform or crack when subjected to a certain external force.

Deformation of the rim can cause shaking when driving, uneven weight of the rim can also cause shaking when driving, and incorrect angle of the rim can also cause shaking when driving.

4. Throttle problems.

The most common cause of car shake may be a dirty throttle valve and excessive carbon build-up in the fuel injector. After the car travels for a period of kilometers, the throttle valve will be too dirty to cause the throttle to close loosely or the idle motor to stagnate, resulting in the engine idling speed is too high, and the carbon deposits generated by the engine in this process will also cause the vehicle to shake, especially when starting the vehicle, the engine will shake more than normal, and even sometimes there will be a phenomenon that can not be started at one time. Therefore, when the body shakes, the first thing to do is to check the throttle and fuel injectors.

If you find that the throttle valve is too dirty or the fuel injector has too much carbon deposit, you should clean it with fuel injector cleaner or throttle cleaner in time.

5. The oil pressure is unstable.

If you still find that the body shakes after these are finished, it is recommended that you go to the repair shop to check whether the fuel supply pressure and intake pressure sensor are normal, if the oil pump supply pressure is not normal, the intake pressure sensor is wrong and improper work will cause the body to shake.