The emergency Check Engine gauge (the powertrain icon on the dashboard) is simply called “check” by motorists. Check Engine literally translates as “check engine,” but drivers call it “throw out the engine”! If this light comes on, it means that there is a big problem in the power plant or other important system of the car, and it is frightening. But in certain situations, the indicator blinks for a while and then goes out – it all depends on the specific malfunction.
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How Check Engine Works
The system works as follows:
- The electronic engine control unit records the problem;
- sends it to the memory in the form of a code;
- At the same time, it gives a command to turn on the Check Engine.
It should be noted at once that the “check” always lights up without any prior warning. And at once it is impossible to understand what exactly has happened to the engine. Even if you are the happy owner of a BMW, Audi, Porsche, Mercedes or Volkswagen, where there is a diagnostic that scans all systems of the car for errors, the deciphering of the causes of the Check Engine will not be displayed on the panel.
You can try to detect the problem with a diagnostic scanner. It is connected through a connector or a laptop with special software.
The illuminated Check Engine icon can not be ignored! Let’s understand what unpleasant problems can tell about the flashing “check”, and what to do about it.
Flashing Check Engine problems
- A problem with the ignition of the fuel-air mixture in one cylinder or in several at once. Then the emergency light will blink, but other manifestations the motorist will not feel. However, you should not relax: problems will surely appear later.
- Filling up with low-quality gasoline. Or as a variant – instead of the 95th you fill up with 92. In this case, the engine will detonate, that is “swear at gasoline”, and it is destructive for it. The power decreases, and the engine starts working with failures.
Firstly, never fill up the gas tank at dubious gas stations, and do not buy fuel in cans from dubious sellers. Secondly, don’t be fooled by manufacturers’ and sellers’ assurances that 92-grade gasoline is fine for supercharged engines.
Of course, if you refueled with low-quality or unsuitable fuel just once, the power installation of your auto will not ruin. But with such regular “economy” the problems will be revealed.
You should not dilute bad fuel with good. The low-quality gasoline should be drained completely, and only then refill the gas tank with high-quality fuel.
- Don’t forget to close the cap of the tank, the “check” may blink because of it. The diagnostic program will decide that the fuel system is depressurized and will respond with an appropriate signal. By the way, the depressurized fuel system increases fuel consumption.
If you tightened the cap tight enough, but the icon is still lit, check if there are any cracks in the cap. If in passing the engine knocks, hums or squeaks, it means that the light is on for another reason.
- If the light comes on and goes out a few moments later, it means that one spark plug, coil or injector is not working properly. This usually occurs as a result of a home-made service.
In some engines, replacing spark plugs is difficult enough. More precisely, three spark plugs are easy to change, but to replace the fourth one you need to remove the massive duct that covers it. Unscrupulous masters usually do not get to this spark plug on purpose, not to complicate their work. Exactly it fails, what is indicated by a “check”.
- Failure in fuel injectors. In this case, in addition to the light of the control lamp, you will feel that the gasoline consumption has increased, the power has decreased, at idle – floating revolutions of the motor, when you gain speed the car moves jerkily.
- 6. Faulty elements of the high-voltage system. The indicator also lights up if the wires are worn out or the coils are out of order.
- You may need to replace the oxygen sensor, the so-called lambda probe. This indicator is a part of the exhaust system. It monitors the amount of unburned oxygen in the combustion chamber of the engine. It also helps control fuel consumption.
Malfunction of lambda probe suggests that the onboard computer receives incorrect data, which affects gasoline consumption 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 cause of lambda probe failure is as follows. Over time, the indicator is covered with oil soot, which includes waste and engine oil. As a result, the sensor cannot correctly take readings to adjust the fuel mixture and distribute optimal fuel consumption. Along with increased fuel consumption, the amount of carbon dioxide in the exhaust increases.
If you drive with a faulty oxygen indicator, you may burst the catalytic converter of the car, which is very expensive, as it contains precious alloys. And if you consider that some cars have several catalytic converters, the repair will cost you a pretty penny!
You can replace the lambda probe yourself by carefully studying your car’s manual. But it is impossible not to solve this problem!
- Failure of catalytic converter. With the help of this element, the exhaust of the car engine becomes more environmentally friendly. The catalyst converts carbon monoxide and other harmful compounds into safe substances. In addition to the “check”, malfunction of the catalytic converter is signaled by a twofold decrease in power and acceleration dynamics.
If a car is regularly serviced at a service station, nothing bad usually happens to the catalytic converter. It can fail if a damaged oxygen sensor and spark plugs are not replaced in time. In this case, the catalyst will not convert harmful compounds to safe ones and will eventually overheat.
If the catalytic converter is damaged, it is definitely necessary to replace it, if you do not want to waste extra gasoline and drive with bad traction. You will hardly manage to do it yourself. Therefore, there is only one way out – to address to a service station.
Replacement of the catalyst is a rather expensive repair. Sometimes they try to solve the problem by installing a flame catalytic converter, but it is far from being a hundred percent option.
- Mistakes when installing a catalytic converter. It happens so that the motorist first cuts it out, and then tries to install it back. Why is the catalytic converter cut out? To increase the engine traction. But such actions don’t always lead to the desired result, moreover there is a “bonus”: an unpleasant smell and noise while driving, despite the flame catalytic converter installation. So they put the catalytic converter in its rightful place.
But with improper wiring, the “check” starts signaling, or the oxygen sensor “glitches” (see above).
- Reduced oil level. This can also cause the alarm indicator to turn on. The main thing here is to determine why exactly the lubricant level has decreased. It can be oil burn-out or leakage through oil seals.
- Problems with the fuel pump. Experienced drivers usually notice such a malfunction without a “check”, since the behavior of the car changes.
- Failure of sensors. The system will respond with a “check” if the mass airflow indicator or camshaft position sensor has become malfunctioning in the car.
The task of the mass air flow indicator is to control the amount of air that needs to be added to the fuel for a perfect combustion. This data is constantly transmitted to the on-board computer. If the sensor does not work properly, the fuel consumption increases, the CO2 level in the exhaust increases, the power unit capacity decreases, the acceleration dynamics and smooth running suffer. In cold weather, a car with a faulty indicator is very difficult to start.
The breakdown of mass airflow indicator usually occurs because of incorrect installation of air filter or its untimely replacement (not according to MOT regulations). The sensor itself is not cheap, so very often such a problem is not paid attention to.
But if you ignore it, you may ruin your money on gasoline, because the improper work 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.
When to drive and when not to drive
As stated above, the flashing Check Engine does not always signal a dangerous fault. If the engine does not manifest itself negatively in any other way, you can drive. But there are cases in which it is impossible to continue driving with a blinking “check”:
- if the car’s power has decreased, and the engine has switched to the emergency mode due to speed limitation;
- if the engine began to work unsteadily, vibrate and show other signs of malfunction;
- if indication of the lubricator, catalytic converter and engine overheat turned on simultaneously with a “check”.
If in your car lit up or flashed Check Engine, and you do not have a diagnostic scanner, then be sure to contact the car service. Experienced craftsmen will help identify the problem and “defeat” it. You may need more serious diagnostics and disassembly of some parts. Usually such works are expensive, but engine replacement will cost much more!