When the car starts in the morning, the speed rises first and then decreases very low, and the car s

1.The spark plug loses its ability to ignite.

2.The throttle valve is faulty. Both of these problems can cause engine shake and unstable speed.

3.Carbon deposits can cause insufficient combustion of gasoline and cause the engine to shake. The impact of engine carbon deposition on the car is quite large, first of all, to reduce the engine power, that is, to make the power output uneven and gradually decay, in other words, more and more powerless.

The second is to increase fuel consumption and increase your financial burden. The third is the difficulty of cold start, that is, the difficulty of ignition, it is not easy to get on the car, and finally the carbon deposit in the combustion chamber is strict, and a heavy one will also cause cylinder detonation, and there will be a sound of low-speed acceleration, which will cause damage to the piston and crankshaft, and cause high temperature of the engine, which will seriously affect the safety of the car. Then there is the excessive discharge, which not only fails the annual inspection and inspection, but also directly aggravates the harm of polluting the environment.

The load operation of the transmission will destroy the quality and friction characteristics of the transmission oil, increase the friction and wear, and the transmission noise will follow, and at the same time, the sludge (impurities or dirt) will also be generated inside the transmission (such as the valve body), resulting in the transmission stuttering, disgearing, impact, skidding, stalling, abnormal noise, delay, high temperature, oil leakage, etc. (Audi and other high-end models will call the police and enter the transmission protection mode) If it is not solved in time, the transmission will be scrapped.

Hello! It should be a dirty throttle or a problem with the gearbox computer!!

When in doubt, please ask.

In general, a high idle speed for a cold start is not a fault. Because the high speed of the engine after starting is intentionally controlled by the engine computer, its main purpose is to make the water temperature, oil temperature and three-way catalytic converter quickly reach the optimal working temperature, reduce the wear of the engine transmission, improve combustion efficiency and improve emissions.

All cars have a high idle speed process when starting cold, and the lower the temperature, the longer the high idle speed will be maintained. After ignition, the engine idle speed is generally between 1300-1500 rpm, and the sound of the engine is also very loud, as the water temperature gradually increases, the idle speed gradually decreases, and finally drops to the normal idle speed of about 800 rpm.

In winter, the atomization conditions of gasoline are poor, especially the carburetor vehicle, which is generally not easy to start, even after starting, it cannot be transferred to normal working condition immediately.

Therefore, when carrying out winter maintenance, it is necessary to clean and dredge each oil passage and airway, and check the working condition of the throttle valve, choke valve, accelerator pump and vacuum pump, which should be adjusted to the best state. At the same time, it is also necessary to appropriately adjust the fuel supply concentration of the idle speed to ensure the normal operation of the idle speed in severe cold.

The circuit is mainly to check the platinum gap of the distributor and the electrode gap of the spark plug. The platinum contacts of the distributor should be clean and non-ablative, the contact surface should be more than 70%, and the gap should be between millimeters.

For models using electronic ignition, the spark plug gap is generally between millimeters, and the spark plug gap is too large, and the engine is not easy to start when the car is cold; If the clearance is too small, the engine power output will be reduced, fuel consumption will increase, and exhaust emissions will exceed the standard.

The reason why the idle speed cannot be lowered after the cold start is caused by the failure of the idle control valve of the car. The workaround is:

If the idle control valve of the car is faulty, you need to go to the 4S shop or repair shop of the car in time to repair or replace the idle control valve of the car to solve the abnormal idle speed. Generally speaking, because the car needs to enter the normal working environment as soon as possible after the car starts, the engine computer will automatically inject more fuel when the car is cold, and quickly increase the water temperature of the engine by burning more fuel than the normal idle speed, so that the engine can quickly enter the appropriate temperature. Additional Information:

The introduction of car idle speed is as follows: the power of the engine is the combustion of fuel, and the fuel is completed by the fuel injection system, ignition system, and mechanical structure, so the instability of the idle speed is likely to be due to the abnormality of these systems. For example, air intake system leakage, fuel pressure is too low, air filter is clogged, injector atomization leakage, improper idle speed adjustment, spark plug work poorly, air flow meter failure, etc.

Under normal circumstances, the amount of air intake into the engine must be strictly limited, and if there is an abnormality in the air intake system, throttle, air flow meter, idle control valve, or leakage, it may cause the engine to idle unstable. Reference**: Phoenix.com - Car Owner:

You know the original. Questions. The cold car can not be idled, and the temperature is good after driving for a period of time, and the fuel consumption has been high recently.

You look to see if the center console is in snow mode or if a c is turned on.

Due to long-term low-speed exercise, resulting in carbon deposits, and then unstable idling, causing damage to the engine, solution, 1 cleaning, 2 running at high speed and high speed for a period of time.

A large reason is that there is too much carbon deposit, especially at the intake valve, which is easy to absorb the mixed oil and gas, especially the low starting speed, resulting in an imbalance in the air-fuel ratio, causing the engine to surge and then stall. When starting again, due to the saturation of oil and gas in the carbon deposit, more oil and gas can not be absorbed, and the specified air-fuel ratio is reached, and the short-term concentration of oil and gas becomes larger, which helps the engine to ignite, with the heating of the temperature, the oil and gas in the original carbon deposit evaporates, and returns to normal.

Preface: Friends who often drive will notice that when the cold car is started, the speed of the car will be very high, what is the reason for this? Is there any harm to the vehicle? Let's take a look! <>

1. The reason for the high speed when the cold car starts. Before the cold car starts, the engine temperature of the car is very low, and if the atomization effect of the car is not good, in order to achieve the corresponding gasoline combustion conditions, the engine will increase the amount of fuel injected accordingly, which will lead to too high speed. But when the water temperature of the engine rises to a normal temperature, the revs will drop and will continue to drop to the normal range.

When the speed of the soup cold car is as high as about 1,800 revolutions per minute, it is necessary to go to the auto repair shop to check the temperature sensor of the car.

and does the throttle need to be cleaned and replaced? <>

2. Precautions when starting the cold car. There are many issues that need to be paid attention to when starting a cold car to prevent increased wear and tear on the car. When starting the vehicle at low temperature, it is undoubtedly the time to cause the greatest damage to the vehicle, because the engine oil in the cold and warm conditions can not fully play its lubrication function, so after starting the vehicle at low temperature, it is necessary to drive slowly and not slam on the accelerator to increase the speed.

And because the cold car has not been started for a long time, the temperature of each part of the vehicle is very low. Therefore, after starting the cold car, it is necessary to hang the low-speed gear and transplant it slowly, which is not only to reduce the burden on the engine, but also for the tradition of the car, when the various components of the system are warmed up, the other parts of the car are still in a low temperature state. <>

Third, the purpose of regular maintenance of the car and in order to increase the service life of the car, to carry out regular maintenance of the car, small maintenance only needs to replace the oil and filter element of the car, and large-scale maintenance requires the owner to do the corresponding inspection and maintenance services on the various parts of the car within the time limit specified by the manufacturer, so as to ensure that the car is safer in the driving process.

It's a problem with the engine, or the temperature sensor is faulty, which is a case, because when the car is just started, the temperature is relatively low, and the speed will be very high, and when the temperature drops, the speed will return to normal.

It could be because of a problem with the car's engine, or it could be because the car has been left in a cold place overnight. At this time, the parts of the whole vehicle are cold, so this problem will occur at this time.

It may be caused by the high engine speed of the car when starting the car, and it may be caused by improper operation.

The water temperature is fine when it is normal. No problem, it was cool in the morning or for a long time to park the car, and the engine water temperature did not reach the normal temperature. The mixture supplied by the engine computer is thick, and the oil supply is small, which cannot meet the lubrication requirements, so the speed is high and the sound is loud or the work is unstable and the exhaust smell is large, and as the engine gradually heats up, it slowly returns to the normal idle speed and work.

Dear, this question is up to me, it takes a little time to type, please be patient, thank you!

This situation is mainly due to the fact that the temperature is particularly low when the engine is cold start, and the oil supply of the engine is relatively large, the engine burns poorly, and the engine produces more carbon deposits, which will lead to this phenomenon, mainly the need to clean the carbon deposits of the engine, clean the throttle and fuel injector, replace the spark plug, and check the carbon in the engine cylinder. If there is a lot of low carbon, it also needs to be cleaned.

Questions. Does the impact open.

This does not affect the driving, that is to say, the cold car start is only this phenomenon, as long as this is normal driving, as long as the ignition is not turned off, then it can be used normally.

Questions. The starting car will shake the fault code, and it will be good to start again.

Yes, even in the case of shaking, the computer will think that the engine is not working properly and there will be a fault light. This has time, go get this. You can clean all the carbon deposits of the engine.

Questions. It should be replaced, and it has not been cleaned well, and it is good and bad.

In this case, you need to check the inlet air temperature sensor and water temperature sensor to see if there is any problem, and you need to check the atomization effect of the fuel injector.

Questions. Can the fuel injector be washed, the store said that six must be replaced with new ones, and said that they can't be cleaned.

It can be washed, no problem. It is also possible to check the atomization effect.

1. Injector failure, 2The inlet filter of the fuel injector is clogged with sedimentary material, 3Carbon deposits on the head of the fuel injector cause the needle valve to get stuck, resulting in a smaller amount of gasoline injection or poor atomization. 4.Check the oil pump for damage.

The main reason for this is that the engine does not reach the normal working state, and the ECU will increase the amount of fuel injection by default, which leads to an increase in engine speed. At the same time, if the working condition is not good, the power will not be high, and the power will be insufficient.

When starting the vehicle in winter, first turn the ignition switch in one gear, then the water temperature indicator on the dashboard will light up, and it will take about a few seconds for the indicator light to turn off automatically, and then you can start the starter and start without idling.

The working efficiency of the engine is related to the water temperature, the experiment proves that the water temperature below 40 will consume more fuel 6%, the winter car should appropriately extend the low-gear driving time, control the speed within 3000 rpm, wait for the water temperature and lubricating oil temperature to rise and then enter the normal driving. In addition, you should also pay attention to the water temperature during driving, generally speaking, 70 -90 water temperature is ideal.

Hello, it is normal for the engine speed to be high when the cold car starts, at this time the car is not hot, the oil is thick, and the acceleration will be slow.

Hello, this phenomenon is because the engine is not yet in normal working condition, so the rev speed is high and the acceleration is slow.

It is normal for the engine to rotate at a high speed when starting from a cold car, but the acceleration is relatively slow because of the high viscosity of the cold car oil.

Hello, the idle speed of cold car start is relatively high, this is due to the engine has not yet entered the normal working state, just wait a few minutes to warm up.

Hello, the idle speed of the cold car start is relatively high, so the speed will be very high, and the starting power is not very sufficient, which is normal.

It seems to you that this situation is very normal, and this situation is mainly due to the engine temperature being too low and the engine rpm increases.

Cold start, the run-in degree between the parts is average, and it takes about 3 minutes to warm up the car to get a better speed.

I drove in the morning and waited for the speed to come down and then walked, but why did I just step on the accelerator and only saw the speed going up, the engine was very loud, but the speed couldn't go up, it was almost 20 miles, and the speed came down after a while, and the speed went up? All -5s are like this, or is it a problem with my driving!

The reason why the engine speed is very high when starting is mainly because the car is still "waking up and adjusting the state" at this time, and the car will become a little higher at the beginning in order to achieve a successful awakening, so that the on-board computer can adjust the various parts of the car in a short time to realize the adjustment of the state.

For example, if the car's lubrication system is re-established, after completion, the on-board computer has become familiar with the current state of the car, so that the speed can be kept very low, so as to save fuel consumption and reduce engine wear.

Of course, the time for adjusting the state of the car is also different in different circumstances, for example, in winter, the temperature is very low, so it takes longer for the car to reduce the speed from the start to the normal idle state, and the initial speed level of the engine will be higher, and some cars can even reach 2000 rpm.