What's wrong with the engine emission warning light?

In life, sometimes we will encounter the situation that the car engine fault light is on. What is the reason why the car engine fault light is on? Let's talk about the relevant content together.

What is the reason why the car engine fault light is on?

When the computer receives the parameters of the oxygen sensor and the exhaust emission seriously exceeds the national legal standard, the internal program of the computer cannot be corrected to the standard range. At this time, the engine control computer will send a warning light (yellow pollution light is on) through the instrument to remind the owner to go to the maintenance station to check the reason why the engine pollution emission light is on.

Next, let's take a look at the analysis of automobile engine fault lights:

Fault phenomenon: it is difficult to start the cold car in the morning or it is unstable after starting, which may be accompanied by flameout or light pollution. Sometimes after the flameout, restart the engine and the pollution lamp disappears. Sometimes after restarting, the engine vibrates normally, but the pollution lamp lights up.

The principle of this fault is:

1. The process of converting chemical energy into mechanical energy is the reaction of thermal energy.

2. Analyze the specific reasons why the fault light is on.

When the engine is cold, the cylinder wall and other parts of the engine are cold metal parts. When the engine is running, the engine oil sprayed by the injector is atomized into the cylinder, and the atomized mixture meets the cold cylinder wall and condenses on the cylinder wall, which is not conducive to the ignition and combustion of the engine. If the temperature of the engine cylinder wall is very high, the mixture entering the cylinder will not condense and vaporize when it meets the boiling wall, and the vaporized mixture at high temperature will contribute to the combustion of the mixture, thus contributing to the smooth and normal operation of the engine.

Engine jitter means that the mixture in the cylinder is not completely burned, so it will be engine jitter. In the process of engine exhaust, the incompletely burned mixture will be discharged through the exhaust valve. At this time, the oxygen sensor is installed in the exhaust pipe. Its function is to check the oxygen content in the exhaust gas. The more fully the mixture is burned in the cylinder, the less oxygen it contains. On the contrary, the more oxygen it contains. The oxygen sensor uses this working principle to detect and convert it into an electrical signal that can be recognized by the computer, and then send it to the engine control computer. According to the set software program, the computer collects the working parameters of the engine through various sensors on the engine, and sends them to the ignition system and fuel injection system after correction and calculation. After receiving these working instructions, these systems will correct working parameters and complete ignition and fuel injection. At this point, the engine has entered the work of re-ignition and combustion, so the work adjustment is repeated.

When the computer receives the parameters of the oxygen sensor and the exhaust emission seriously exceeds the national legal standard, the internal program of the computer cannot be corrected to the standard range. At this time, the engine control computer will send a warning light (yellow pollution light is on) through the instrument to remind the owner to go to the maintenance station to check the reason why the engine pollution emission light is on.

Causes of lamp pollution:

1. Poor gasoline quality will lead to incomplete combustion of the mixture in the cylinder, which in turn will lead to pollution of the lamps and easy carbon deposition.

2. The existence of carbon deposits at the air inlet and piston top will lead to poor atomization, insufficient combustion and light pollution.

3. When the cold car starts, especially when the weather temperature drops sharply, the pollution light will light up when the computer starts because of the temperature correction problem, but as long as the temperature drops to a certain temperature and there is no fluctuation, it will be relatively stable.

4. If the mileage of the engine is too long, the working characteristics of the spark plug will be weakened and the pollution lamp will light up.

5. Too much carbon deposit and difficult ignition will lead to reverse breakdown of the ignition coil, which will lead to the failure of the ignition coil, poor ignition, and lead to incomplete combustion to produce polluted light. A remarkable feature of this phenomenon is that the engine always shakes violently when the ignition coil fails. If the vibration is not always severe, the ignition coil can be basically omitted.

6. The vehicle is too old, mechanical aging leads to poor working condition of the engine, and poor combustion and ignition leads to lamp pollution.

7. Some sensor computer boards have their own faults, resulting in lamp pollution.

8. Other reasons, etc. ,

There are many reasons for lamp pollution, but the first three are the most important. Special attention: When the pollution light is on, the engine will not shake or slightly shake. At this point, the owner does not need to worry when using it. It can be used normally, and sometimes it is convenient for inspection or maintenance.

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