The Check Engine emergency sensor (the icon of the power unit on the dashboard) is simply called by motorists a “check”. Check Engine literally translates as “check the engine”, but drivers call it “throw the engine”! If this light comes on, then there is a big problem in the power plant or other important system of the car, and this is scary. But in certain situations, the indicator flashes for a while, and then goes out – it all depends on the specific malfunction.
1. How the Check Engine works
The system works as follows:
– the electronic control unit of the motor fixes the problem; – sends it to memory in the form of a code; – simultaneously gives a command to turn on the Check Engine.
It is immediately worth noting that the “check” always lights up without any prior warning. And it is immediately impossible to understand what exactly happened to the engine. Even if you are a happy owner of a BMW, Audi, Porsche, Mercedes or Volkswagen, where diagnostics are provided that scan all machine systems for errors, the decoding of the causes of the Check Engine will not be displayed on the panel.
You can try to detect the problem using a diagnostic scanner. It is connected via a connector or a laptop with special software.
The Check Engine icon that is lit cannot be ignored! Let's figure out what unpleasant problems a flashing “check” can tell about, and what to do about it.
2. Blinking Check Engine Issues
1. The problem with the ignition of the air-fuel mixture in one cylinder or several at once. Then the emergency light will blink, but the motorist will not feel any other manifestations. However, you should not relax: problems will definitely appear later.
2. Refueling with low-quality gasoline. Or as an option – they filled in instead of the 95th 92nd. In this case, the engine will detonate, that is, “swear at gasoline”, and this is fatal for him. Power is reduced and the engine starts to run rough.
Firstly, never fill up the gas tank at questionable gas stations, and also do not buy fuel in cans from questionable sellers. Secondly, do not be fooled by the assurances of manufacturers and sellers that 92nd gasoline is also excellent for supercharged engines.
Of course, if you refueled with low-quality or inappropriate fuel one time, then the power plant of your car will not fall apart. But with such regular “savings”, problems will definitely make themselves felt.
Do not dilute bad fuel with good. Low-quality gasoline must be drained completely, and only then fill the gas tank with high-quality fuel.
3. Do not forget to close the tank lid, the “check” may flash because of this. The diagnostic program will decide that the fuel system is depressurized and will respond with an appropriate signal. By the way, due to depressurization of the fuel system, fuel consumption increases.
If you tightened the gas filler cap tight enough, but the icon still glows, look for cracks in the cap. If along the way the motor knocks, buzzes or creaks, then the signal lit up for another reason.
4. If the light comes on and goes out after a few moments, this means that one spark plug, coil or nozzle is not working properly. This usually happens as a result of artisanal maintenance.
In some engines, replacing candles is quite difficult. More precisely, three candles are easy to change, and to replace the fourth, you need to dismantle the massive air duct that closes it. Unscrupulous craftsmen usually don’t get to this candle on purpose, so as not to complicate their work. That's it, and it fails, which is signaled by the “check”.
5. Faulty fuel injectors. In this case, in addition to the light of the control light, you will feel that the consumption of gasoline has increased, the power has decreased, at idle – floating engine speeds, when picking up speed, the car moves in jerks.
6. Malfunctions of the elements of the high-voltage system. The indicator lights up even if the wires are worn out or the coils are out of order.
7. It may be necessary to replace the oxygen sensor, the so-called lambda probe. This indicator is part of the exhaust system. It controls the amount of oxygen not burned in the combustion chamber of the internal combustion engine. It also helps to control fuel consumption.
A malfunction of the lambda probe indicates that the on-board computer of the car is receiving incorrect data, and this affects gas mileage and engine power. Most cars have 2-4 oxygen indicators. If you have a home car scanner, you can find out which indicator needs to be replaced.
The reason for the failure of the lambda probe is as follows. Over time, the indicator becomes covered with oil soot, which includes used and engine oil. As a result, the sensor cannot correctly take readings to adjust the fuel mixture and distribute the optimal fuel consumption. As fuel consumption increases, the amount of carbon dioxide in the exhaust increases.
If you drive with a faulty oxygen indicator, the auto catalyst may burst, which is very expensive, since it contains precious alloys. And if you consider that there are several catalysts in some cars, then the repair will cost you a pretty penny!
You can replace the lambda probe yourself by carefully studying the manual for your car. But it is definitely impossible not to solve this problem!
8. Malfunction of the exhaust gas catalyst. With the help of this element, the exhaust gases of an automobile engine become more environmentally friendly. The catalyst converts carbon monoxide and other harmful compounds into safe substances. In addition to the “check”, a malfunction of the catalyst is signaled by a twofold decrease in power and acceleration dynamics.
With regular maintenance of a car at a service station with a catalyst, usually nothing bad happens. It can fail if you do not change the damaged oxygen sensor and spark plugs in time. In this case, the catalyst will not convert harmful compounds into safe ones and will eventually overheat.
If the catalyst is damaged, then it definitely needs to be replaced if you do not want to waste extra gasoline and drive with poor traction. It is unlikely that you will be able to do it yourself. Therefore, there is only one way out – to contact a service station.
Replacing a catalyst is a rather expensive repair. Sometimes they try to solve the problem by installing a flame arrester, but this is far from a 100% option.
9. Errors when installing the catalyst. It happens that the motorist first cuts it out, and then tries to put it back. Why cut out the catalyst? To increase engine thrust. But such actions do not always lead to the desired result, besides, an unpleasant smell and sound appear when driving, despite the installation of a flame arrester. So they put the catalyst in its rightful place.
But if the wiring is incorrect, the “check” starts to signal, or the oxygen sensor “bugs” (see above).
10. Decreased oil level. This may also cause the alarm indicator to turn on. The main thing here is to determine why exactly the level of lubricant has decreased. This may be oil burnout or leakage through the seals.
11. Problems with the fuel pump. Experienced drivers usually notice such a malfunction even without a “check”, since the behavior of the car changes.
12. Failure of sensors. The system will respond with a “check” if the mass air flow indicator or the camshaft position sensor has become incorrect in the car.
The purpose of the mass air flow indicator is to control the amount of air that must be added to the fuel for perfect combustion. This data is constantly transmitted to the on-board computer. If the sensor does not work correctly, then the fuel consumption increases, the level of CO2 in the exhaust rises, the power of the power unit decreases, acceleration dynamics and ride smoothness suffer. In cold weather, a car with a faulty indicator is very difficult to start.
A failure of the mass air flow indicator usually occurs due to improper installation of the air filter or its untimely replacement (not according to the maintenance regulations). The sensor itself is not cheap, so very often such a problem is not paid attention.
But if you ignore it, you can go broke on gasoline, because the incorrect operation of the indicator increases its consumption. In principle, you can change the sensor yourself, but in car services this work is inexpensive and takes very little time.
3. When you can drive, and when you can't
As mentioned above, Check Engine flashing does not always signal dangerous malfunctions. If the engine is no longer negatively manifested, then you can move. But there are cases in which it is impossible to continue driving with a flashing “check”:
– if the power of the car has decreased, and due to the speed limit, the engine has switched to emergency mode; – if the motor starts to work unstably, vibrate and show other signs of malfunction; – if at the same time as the “check” the indication of the oiler, catalyst and engine overheating turned on.
If the Check Engine caught fire or flashed in your car, and you do not have a diagnostic scanner, then be sure to contact a car service. Experienced craftsmen will help identify the malfunction and “defeat” it. More serious diagnostics and dismantling of some parts may be required. Usually such work is not cheap, but replacing the engine will cost much more!