1200 rub. for the photo report
We pay for photo reports on car repairs. Earnings from 10,000 rubles/month.
Write:
Error code P0300 indicates a violation of the ignition order , which stands for random multiple misfires of the cylinders ; in English, the diagnostic tool displays: “Random cylinder misfire detection system.” If a misfire is detected in a specific cylinder, then the last digit “P030x” will change to 1, 2, 3, 4 and so on up to 6 or even 12, depending on which particular “pot” the misfire is in. So error P0300 is derived from errors such as P0301, P0302, P0303, P0304. Most often they occur due to a lack of spark, a fuel supply failure or problems with the exhaust gases.
Let's look at the list of possible causes of misfires, why error p0301, error p0302, error p0303, error p0304 or others of this kind appears, the consequences and methods of elimination, in more detail.
Cylinder failure: causes and diagnostic methods
Issues discussed in the material:
- Why does cylinder failure occur in an engine?
- What is the danger of cylinder failure?
- How to independently identify the cause of cylinder failure
While driving a car, did you feel that the power unit was vibrating, while its power dropped, and it began to consume more fuel? Does the car start only the second or third time? These signs indicate that a cylinder failure has occurred. In our article today we will look at how to fix this problem.
Consequences of error P0300
If a misfire occurs in the engine in the exhaust pipe the level of exhaust gas toxicity increases , which, in turn, can also lead to an increase in the temperature in the catalyst, which causes its damage (the honeycombs melt because the temperature exceeds the threshold of 800 °C ). On some cars, in order to reduce the burnout of fuel in the catalytic converter and, consequently, the level of toxicity, the ECM unit monitors the frequency of misfires using crankshaft and camshaft sensors and, in addition, it registers error p0300, signaling a checkengine light can also , in which the gap was discovered. It is worth mentioning that most often, for some reason, the owners of cars such as Lacetti, Matiz, Priora and other injection VAZs, as well as Opel, Nissan, Kia cars, are interested in the reasons for the occurrence of this error.
Why does the engine troit?
Some car owners do not know why the engine idles at idle. If you are an inexperienced driver, you need to identify this malfunction and then find the reason why it occurred.
Cylinder failure is a good reason for the engine to misfire. The cylinders may stop functioning alternately. Moreover, you don’t even need to search for a breakdown, because it will immediately become clear that a cylinder failure has occurred. The engine will shake and vibrate, the speed will begin to jump, it will be difficult to start the car, and the car will begin to consume more fuel. It is simply impossible to ignore such symptoms. For example, if one cylinder fails in an engine that has only 4 of them, the speed will drop by 25%. Even an inexperienced driver will notice this malfunction.
Signs of engine tripping
How to determine if a cylinder has failed:
- After a cylinder failure, the power unit will shake at idle speed. Unfortunately, an inexperienced driver is unlikely to notice this immediately after a breakdown. The fact is that this symptom occurs over time. And if you notice that the engine is shaking, it means that the problems started a long time ago. And after the cylinder failed, the engine worked for a long time and became worn out.
- The spark plug became dark, smoked, and carbon deposits formed. This sign indicates that the spark plug should be replaced. But this is at best, and at worst, such a symptom means that the machine is not working properly. Even though spark plugs can be used for quite a long time, they should not be sooted. A slight change in shade is allowed.
- The exhaust system began to sound differently. This also indicates a cylinder failure.
- If the car picks up speed poorly, both at low and high speeds, then the engine is not functioning properly. The reason could be either a cylinder failure or another engine failure.
- The car began to consume more fuel. In this case, you should definitely check the operation of the engine. This symptom indicates a serious problem with the motor.
We recommend
Summary
So, we looked at why the car is tripping. These are not all possible reasons, but they help to accurately diagnose the operation of the motor and find the malfunction.
Comrades, help out! The situation is this, I have a Priora, 1.6 16 valves, the engine starts to stall after the car warms up... It works fine when cold. The BC shows misfire errors, and in all cylinders it is chaotic... I changed the spark plugs, there are new ones... BUT, if you disconnect the block from the mass air flow sensor, the tripping goes away, it works like a clock without the mass air flow sensor, the speed is kept around 840 at idle and misfire errors do not appear... So I drove it for 2 weeks, I thought there was a problem with the mass air flow sensor, but today I installed a known working mass air flow sensor, taken from another Priora, in which everything is fine, but the situation has not changed, it’s the same... Where to look?
What does driving with an inoperative engine cylinder lead to?
When a cylinder fails, the fuel mixture entering it does not burn. The fuel is mixed with oil, removing it from the cylinder bore. The mixture will then penetrate into the crankcase. Due to the fact that the surface of the cylinder is dry, scoring occurs on it. In addition, oil mixed with fuel does not lubricate healthy cylinders well.
As a result of the failure of the first cylinder, the others will also stop working normally. Where will all this lead? The car owner will be forced to spend a large sum on boring the cylinder block or even on lining.
The next problem that will happen if the cylinder fails is that the engine will overheat. The change in its operating temperature is due to the fact that the lubricant does not perform its functions. And, as you know, motor oil not only lubricates surfaces, but also removes heat.
All of the above is sufficient reason to declare: under no circumstances should you operate a car after a cylinder failure!
Where to look for the cause of cylinder failure
Important!
You will have to look for the cause of engine cylinder failure in a garage. There are two possible ways here: check the mechanics or the electrical, that is, the ignition. Let's start with the simplest thing and diagnose the electrical system.
- Spark plug . Let's use a proven method to check their functioning. Look at the side electrode and insulator, their color should be light brown, not black. There should also be no soot. If there is soot, it means the mixture is over-enriched or there is oil on it. Now let's start checking sparking. Place the spark plug on the high-voltage wire, and then bring it to the cylinder block, the distance between them should be 1-2 cm. Turn the starter. Did the spark travel that distance? This indicates that the spark plug is working properly, otherwise it should be replaced.
- BB wires . They may be damaged. How to check this? Pay attention to the tip of the high-voltage wire. Did you see a light gray coating on it? This means he is operating at the limit. Use a special multimeter to check the resistance of the high-voltage wire. Please note that depending on the motor, the wire length and resistance may vary. When there are no additional instructions, 20 kOhm is taken as a constant resistance value. If this value is exceeded, then the problem is in the high-voltage wire.
- Ignition distributor . When the spark plug does not work properly, a breakdown occurs in the ignition distributor cap. In this case, it is necessary to diagnose the ember; stretching the spring will also help.
- High voltage wires are mixed up . If a cylinder failure occurs, the cause may be in the explosive wires.
We recommend
Now let's check the mechanics.
- Injector . A malfunction in its operation may be one of the reasons for the failure of the cylinder. For example, an injector is broken, or the injector is clogged with a poor quality fuel mixture. Note! Damage can result from the use of the latest fuel purifiers, which can be purchased at any specialized auto store. It is best to diagnose and clean the injectors at a trusted service center.
- Gas distribution mechanism . The fuel mixture enters the cylinders in the wrong quantity and quality. This can happen for various reasons. For example, the timing belt was installed incorrectly, the tensioners or oil seal became unusable. The camshaft may also break, or the hydraulic lifters may need to be replaced.
Because the engine constantly overheats, the cylinder head gasket may burn out. This happens because the car owner does not monitor the antifreeze level or drives the car at high speed.
All of the above can cause the cylinder to fail. By the way, not everything that can lead to such a breakdown is listed here. Only by understanding why one cylinder in the engine failed will you be able to eliminate the problem. You can do this yourself or by visiting a specialized service center.
Nutrition
A missed flash may occur due to the fact that there is simply nothing there to burn, that is, to flash. So first, start the engine. When it has been running for a couple of minutes, turn it off and remove the spark plug. If it turns out to be dry, then the reason is the lack of fuel. There may be several reasons for this situation:
- The most common cause of 16 valves on a Priora is damage to the injector winding. You can check this by removing the cover and manifold. Then measure the resistance on the injector winding; it should be within 15-15 Ohms. If it is faulty, it should be replaced. Read more about how to do this in the article “How to check an injector nozzle”;
- Another reason is a clogged injector. This usually happens when using low-quality fuel. You can also “clog” these engine elements yourself by pouring various cleaners into the tank. They partially destroy sediments. Which, in the form of a suspension, enter the injector, where they get stuck in the nozzles. To fix the problem, you need to flush the injectors. You can do this yourself without removing them from the engine.
Diagnostic methods
When you find out that the motor is not working, you should diagnose it. This is the only way you can find out which cylinder failed and why. You can do this yourself, or go to a car service center. There the engine will be checked using a computer. However, most often you will be able to find out on your own why the engine is tripping. However, if there is a cylinder failure, and the reason is a decrease in compression, you should find a competent specialist who will solve your problem.
Replacing spark plugs yourself
Replacing spark plugs on a Lada
Since faulty spark plugs occur most often during acceleration failures, auto mechanics recommend Lada Priora owners learn how to change this element of the ignition system themselves. This should be done after the car has traveled 20 thousand km. However, if the engine starts to trip, the spark plugs should be replaced before this date:
- Initially, you will need to clean the engine compartment from dirt and debris,
- Next, it is necessary to dismantle the engine elements to gain unhindered access to the spark plugs. Adapters and extensions are used for this. Before performing this work, you will need to wait until the engine has completely cooled down.
- The spark plugs are unscrewed one by one, and the high-voltage wires are disconnected. To prevent an accident, you must first remove the battery from the car. Otherwise, electricity may be supplied. When performing this procedure, it is recommended to monitor the force applied. It is better to seek help from specialists if the candle does not budge.
- To prevent debris from getting into the resulting holes, you need to cover them,
- The candles are screwed in manually at the first stage. Next, they are tightened using a special mechanism that allows you to measure the amount of force applied,
- high voltage wires are connected,
- engine operation is checked,
- The previously dismantled elements are assembled in the reverse order.
To ensure stable engine operation, spark plugs should be replaced regularly.
Lada Priora is the leader among domestic cars; sales of modern vehicles are breaking records. Among the advantages of the Priora, the owners note a good engine, which has better dynamics compared to other Lada models; the interior is also very comfortable. However, it is not without problems, for example, an engine designed for 8 or 16 valves often suffers from problems.
How to prevent the engine from stalling
After you check the motor and find out why it is misfiring, you should fix the problem. When spark plugs or explosive wires fail, it will be easy to solve the problem: just replace them. We take exactly the same actions if the ignition coils or switch are broken. However, when the fuel or air system is clogged, it will not be possible to quickly eliminate the breakdown. To clean the injectors, you will have to use a cleaning compound, such as Injection System Purge. It may also be necessary to replace the lambda probe, because it most likely functions incorrectly.
Have you cleaned the injectors, but this did not help fix the problem and the fuel mixture is flooding the spark plugs? Then we replace them. If the engine fails, the fuel pump and other components of the fuel system should be removed and new ones installed. It is not recommended to repair or install old elements. It may also be necessary to replace the air filter and parts of the air supply system if depressurization occurs.
At the very end, we remove errors in the electronic control unit; this may also be the reason that the motor is not working.
Recommendations for checking and troubleshooting
The first thing you should check when misfiring is the explosive wires and ignition coils (module), they often turn out to have broken insulation, a break, or an oily surface. We measure the wires with a multimeter (normal resistance is about 4 - 10 kOhm), in resistance mode, but to check individual ignition coils, you just need to swap places with a known working cylinder and clear the errors again. If the code has changed to the number of another cylinder, then the coil is faulty. The ignition module is more complicated; it needs to be checked with a tester.
