The car shaking during cold start is a common problem of gasoline vehicles。The most fundamental cause of jitter during cold starts or waiting in neutral is poor combustion in the cylinder。Poor burning，The power provided by the car is not enough，The car is shaking。Give a vivid example，Assume the foal uses100It takes 30 minutes of force to pull the car, but if you only use 10% of force60With a small amount of force, of course it will be unable to move and cause shaking.

The first problem a car faces when starting a car with low ignition energy is low temperature，The temperature inside the engine is not enough，The temperature of fuel and lubricating oil is not enough，So more fuel should be injected during cold start to meet the power requirements，The larger the spark plug gap，The smaller the ignition energy。Fuel atomization is not good at low temperatures，seabet myFuel requires higher ignition energy，The car is used for a long time，The ignition gap of the spark plug tends to become larger，Causes ignition energy to decrease，Thus affecting the dynamics，Cause the car to shake。Also，Ignition coil aging、The high-voltage wire of the spark plug is aging or leaking，Can also lead to reduced ignition energy。

seabet loginInappropriate mixing ratio

Incorrect oil and gas mixture ratio，Exists in both open-loop and closed-loop control。In a closed-loop controlled car，The minimum operating temperature of the oxygen sensor is370℃, if the car has just been started, the temperature in the exhaust pipe cannot be reached370℃, so the oxygen sensor is not working. at this timeECUError in judgment，It mixes oil and gas through the actuator、There is an error in the control of ignition time，Thus reducing the power output of the car，Jittering occurs。

2.Carbon deposits on valves and intake ducts

If carbon deposits occur in the valves and intake passages in the engine，Because carbon deposits can absorb the right amount of fuel (just like water flowing through a river bank，Soil absorbs water)，ECUThere is an error in judgment.

Computer actual control spews out assumptions100portion of oil and gas, but only90shares(10parts are absorbed by carbon deposits), then even if the remaining90Parts of mixed oil and gas are fully burned，The same cannot achieve the required power，Jitter is inevitable。

3.The working conditions of each cylinder are different

Same，Spark plugs in multi-cylinder engines will also have the above problems。After prolonged use，The ignition gap and time control of the spark plug will be different，ButECUThis deviation seabet iocannot be diagnosed，Still treat "them" equally，There is a gap between practice and theory，As a result, the power generated by some cylinders is too small，Will cause jitter。

After the engine has been used for a long time，The clearance between each cylinder liner and the piston will also be larger or smaller，The existing gap is large，Some gaps are small。At cold start，No good engine oil lubrication，Cylinders with large gaps are prone to leaking a certain amount of high-temperature gas from the gaps，Thus reducing power output。

4.Water temperature sensor failure

If you have a fever，But the reading on the thermometer is normal，What will happen？The water temperature sensor is one of the important basis for the computer to judge the engine working condition at that time。If the engine temperature is below zero when starting from cold10Celsius, but the sensor "tells" the computer "the current temperature is20Celsius", then the computer will press20Fuel injection at degrees Celsius，Of course the oil volume must be small，Jitter is of course natural。

5.Other factors

The air flow meter is dirty, resulting in reduced air intake;EGR(Exhaust gas recirculation) valve is not working properly，Introducing exhaust gas at idle；Idle motor control bypass air intake，To adjust the air intake volume，If the voltage is low, it may not work properly；Oil quality is too poor，Cannot reach the corresponding calorific value，The power output resulting in combustion is too small。The above four factors can lead to poor combustion of a certain cylinder during cold start or waiting in neutral，Thus causing engine vibration。