What is the reason why the car engine failure light keeps on

1. Identify the cause of the failure. For diagnostics of such faults in which the engine does not start, the battery should be tested first. It is necessary to find out if the engine does not start because the battery is insufficient.

2. Detect ignition timing. Timing belt slippage is the root cause of the failure that there is no electric spark and the engine cannot start.

3. Detect the starting system. In the case of faults such as engine failure to start, the first thing to do is to check the circuitry in the engine starting system. From the perspective of the most basic composition, the circuit of the starting system generally includes the following basic parts, that is, the battery, the starting motor and the cable connecting these parts.

Of course, in addition to this, ignition switches, starter relays or solenoid coils, as well as in-vehicle anti-theft systems, are also important components of the starting system.

4. Detect the quality of electric sparks. Once the circuitry of the starting system has been tested and proven to be fine-tuned, attention should be focused on why the engine is not working. Generally speaking, the ignition system of the engine is tested first, which is also the easiest inspection job.

In early ignition systems, you could easily remove the ignition coil and use a spark detector to detect if the spark was normal. When choosing a spark detector, an adjustable detector is preferable to a fixed design because it allows you to adjust the detector to a smaller gap so you can tell if there is no spark at all, or if there is an electric spark but it is weak.

5. Detect the fuel system. The diagnosis of the fuel system can be divided into two parts: the diagnosis of the fuel supply system and the diagnosis of the injector circuit system.

The fuel supply system can be detected by measuring the flow and pressure of the fuel. The best way to measure fuel flow is to inspect the line when there is a load in the fuel supply line.

When the fault light is on, it means that the vehicle has a fault code, and at this time, the fault code will be recorded when the ECU is uninterrupted. To the 4S store, the reader can be used to determine the fault code and the corresponding fault content. It is recommended to go to a 4S shop for repairs.

In addition, after the vehicle generates a fault code, it cannot be automatically eliminated if the ECU is uninterrupted or eliminated by using an instrument. Therefore, please confirm that the last fault code was completely eliminated.

In addition, every time you go to the 4S shop, please let it clearly record the maintenance content and fault content, according to the provisions of China's after-sales service law, the same fault can not be solved more than 3 times in a row can not be solved, you can return the car.

If the fault light of the engine is still lit after the ignition, go to detect it, read the fault code, and see if the specific fault is in.

Car engines.

The fault light is always on to indicate it.

Electronically controlled engine.

A fault has been detected by the system.

Engine failure signals are sent by the engine computer, and the ECU controls all the electronic equipment of the entire engine, like:

Electronic throttle.

Fuel injectors. Generators,

Fuel pumps, etc., covering various systems such as air intake, exhaust, fuel, ignition, timing, etc. If the engine fault light is on, what is the specific cause? It can only be detected by computer. The reason why the engine failure light is on.

First of all, light the fault light, so as to tell the owner that the current engine system is faulty, and it should be checked and repaired in time. Secondly, will put this fault.

Information storage. Get up and provide it to the mechanic as a reference when repairing so that the fault can be solved faster. In addition, in order to ensure that the engine can continue to run in the event of a failure, if the detected fault has little impact on the operation of the engine, the computer will directly ignore it, but in fact, the engine is not in good working condition at this time. If a serious fault is detected, the computer will start the emergency program, and the engine can also work under the emergency program, but generally only to ensure that the engine can continue to run without turning off.

For this case, we need to make a preliminary judgment work:

Place the car battery.

The positive or negative pole is de-energized, disconnected for a few seconds, and then installed. After that, start the car and see if the engine fault light will be lit when the instrument is still on, which means that there is no problem with the engine and there is no need to go to the repair shop to check. Part.

A lot of data will be lost after the power failure of high-end cars, which needs to be reset and should be cautious when the power is off. After doing this, you may encounter three situations:1

The light went out just after I got it down, but it came back a few days later. 2.After the power was cut off, the fault light still did not go out.

This situation is that the engine is indeed faulty and needs to be tested by a repair shop.

The vehicle fault light is generally mostly fuel-ejected.

system, you are on the car when the fault light is on.

to start, extinguish, start, extinguish.

After three times after starting the vehicle you observe that the fault light is.

If not, it will still be lit, and if it is still lit, it needs to be timely.

Go to the shop and check the fault code to see if it is the engine.

The problem is still a sensor failure, or it may be even if it does not light up.

If there is a fault, you don't need to go to the store in time to check.

When the fault light is on, it means that the vehicle is out of order.

code, at this time, ECU

In the case of uninterrupted power, therefore.

Defects are recorded. to 4s

shop, use. The reader is able to determine the fault code and correspondence.

of the fault content. It is recommended to 4s

shop for maintenance. Repair. In addition, the vehicle generates a fault code after if.

ECU uninterruptible or eliminated using an instrument is not.

It can be eliminated automatically. Therefore, please confirm the last time.

Whether the code is completely eliminated.

Also, go for 4s every time

shop, please let it be clearly remembered.

Record the content of maintenance and failure, according to the sale of our country.

The post-service law stipulates that the same fault is repaired consecutively3

If you can't solve it more than once, you can return the car.

Answering the sensor question The sensors mentioned here include water temperature, crankshaft position, air flow, intake air temperature, oxygen sensor, etc., when these sensors are damaged, poor contact or signal interruption, the ECU of the car can not accurately obtain the engine data, at this time, it will cause the engine failure light to turn on.

Maintenance ProblemsPoor engine maintenance is the most common cause of engine failure to light up. We know that vehicles have a certain maintenance cycle, if the owner does not maintain on time, coupled with bad driving habits, then it will increase the burden of engine operation, and finally can only remind you through the fault light that you should care about your car.

Oil quality problem here includes fuel and oil, we know that the fuel filled by the car is generally marked, and the oil is also semi-synthetic and fully synthetic, manufacturers generally recommend the owner to use which grade of fuel, which type of oil, if the owner does not add as required, it will cause wear and tear of the engine in the long run, and the fault light is not to blame.

Poor combustion of the engine mixture will be caused by spark plug failure, ignition coil failure, fuel pump failure, oil circuit blockage, etc. Poor combustion of the mixture is caused by engine carbon deposition or knocking problems, and these will eventually be detected by the engine's oxygen sensor, and after being reported to the ECU, the fault light will naturally be lit as a warning.

For your driving safety, please drive your vehicle to the vehicle workshop for inspection as soon as possible.

The function of the fuel system is to supply a certain amount of clean and well-atomized gasoline to the engine according to the needs of the engine's operating conditions, so as to mix with a certain amount of air to form a combustible mixture. At the same time, the fuel system also needs to store a considerable amount of gasoline to ensure that the car has a considerable driving range.

The reasons for the engine fault sign to light up are: 1. Poor gasoline quality will lead to insufficient combustion of the mixture in the cylinder; 2. Carbon deposition in the inlet duct and piston will lead to poor atomization and insufficient combustion; 3. The spark plug is not changed for a long time, and the working characteristics are weakened; 4. Failure of the car sensor.

The engine fault light is not necessarily the engine failure, but more often some parameters exceed the standard value, such as exhaust emissions exceeding the standard, or for some reason the engine fires, etc.

Engine indicator refers to the indicator light used to show the working condition of the vehicle's engine. The indicator light is used to show the working condition of the vehicle engine, when the key door is opened, the vehicle self-test, the indicator light is lit and automatically extinguished, if it is always on, it means that the engine of the vehicle has a mechanical failure and needs to be repaired.

After the engine fault light is on, restart the vehicle or gently test the joints of each wiring harness to check whether the fault light will be turned off to avoid the fault light being lit due to the random connection of the wiring harness.

There are still many reasons, such as excessive carbon accumulation, blockage of air filters, etc.

There will be a portable diagnostic instrument in the repair shop, which can read the fault code, and after obtaining the fault code, you can roughly know what is causing it.

What's going on with the car engine light on? What should I do?

It is normal to be bright during self-inspection, if it is still bright after ignition, it is necessary to go to the maintenance station for inspection in time. The engine fault signal is sent by the ECU (engine computer), and the ECU controls all the electronic equipment of the entire engine, such as electronic throttle valves, fuel injectors, generators, fuel pumps, etc., covering air intake, exhaust, fuel, ignition, timing, etc.

FYI: 1. The sensor is damaged, the contact is poor, or the signal is interrupted; 2. Poor engine maintenance; 3. The quality of fuel and oil is not good; 4. The combustion of the mixture is insufficient; 5. Spark plug failure, ignition coil failure; 6. The fuel pump is faulty and the oil circuit is blocked; 7. The air conditioner filter is blocked.

The specific situation is analyzed as follows; 1. Sensor problems; The sensors mentioned here include water temperature, crankshaft position, air flow, intake air temperature, oxygen sensor, etc., when these sensors are damaged, poor contact or signal interruption, the ECU of the car can not accurately obtain the engine data, at this time it will cause the engine fault light to turn on. 2. Maintenance problems; Poor engine maintenance is the most common cause of engine failure to light up. We know that the vehicle has a certain maintenance cycle, if the owner does not maintain on time, coupled with bad driving habits, then it will increase the burden of engine operation, and finally can only remind you through the fault light to care about your car 3, oil quality problems; The oil quality here includes fuel and engine oil, we know that the fuel filled by the car is generally marked, and the engine oil is also semi-synthetic and fully synthetic, the manufacturer will generally recommend the owner to use which grade of fuel, which type of engine oil, if the owner does not add as required, it will cause wear and tear of the engine in the long run, and the fault light is not to blame.

Poor combustion of the mixture; The failure of the spark plug, ignition coil, fuel pump, and oil circuit blockage of the engine will cause poor combustion of the engine mixture. Poor combustion of the mixture is caused by the problem of engine carbon deposition or knocking, and these will eventually be detected by the engine's oxygen sensor and reported to the ECU, which will naturally turn on the fault light to warn of the intake air intake problem; When the engine burns, it needs to take intake, the air filter element is very important in this process, if the air filter element of the car is not clean, it will affect the air intake of the car if it is not cleaned regularly, and it will be blocked for a long time, and if it is serious, it will cause the engine failure light to turn on. pressurization issues; Intake booster lines and turbochargers can also cause engine failure lights to illuminate.

The most common of these is turbocharger damage, while the vehicle can also experience symptoms such as oil leakage, high oil consumption, loss of power, metal noise, and blue or black smoke from the exhaust pipe. 7. Exhaust problems; Rear oxygen sensor, three-way catalytic converter, exhaust camshaft and bearing. The most common of these is a failure of the three-way catalytic converter that causes the engine failure light to illuminate.

The use of leaded gasoline, the use of leaded or silicone lubricant additives, the bump of the three-way catalytic converter, and the failure of the engine oil supply system are some of the factors that can easily cause the failure of the three-way catalytic converter.

There are several situations in which the engine fault light is on, either it is a problem with accessories or maintenance, or a problem with oil or bad combustion.

1. Accessories problem, the parts problem that causes the engine fault light to light up is mainly the sensor, including water temperature, crankshaft position, air flow, intake air temperature, oxygen sensor, etc., when these accessories are damaged and the contact is poor, the ECU of the car can not accurately obtain the engine data, which will cause the engine fault light to turn on.

The failure of the spark plug, ignition coil, fuel pump, and oil circuit blockage of the engine will cause poor combustion of the engine mixture. Poor combustion of the mixture is caused by the problem of carbon deposition or knocking in the engine.

2. Oil problem, not a big gas station, there is no problem with oil, you can also understand it this way, the underground oil tank of the gas station is cleaned once in February, and the car fuel tank is not so well sealed, so it is natural to clean it regularly.

What are the solutions.

1. The fault of the parts is recommended to go to the maintenance plant in time to check the fault code, replace the parts, 2 fuel oil and combustion is not good, and in the long run, carbon deposits and gum will be generated, as long as the fuel tank is added to the national VI standard fuel additives such as Siyoupu for cleaning, it can also clean and neutralize the impurities deposited in the oil circuit, and discharge it through combustion.

Most of the fault lights without hardware fault codes are caused by poor combustion, when the mixture is not burned well for a long time, it will lead to engine emission failure lights, some show insufficient air intake, some show exhaust failure, and some show oil pressure mixture, etc. Most of them are caused by the oil circuit needs to be cleaned. As long as the National VI standard fuel additive refueling tank runs two tanks of oil, it will be greatly improved.