For example, the Toyota Land Cruiser 200 SUV is equipped with an eight-cylinder power unit. Depending on the number of problem cylinders, this engine can have “seven” or “six”, and so on. However, they still say that “the engine started to misfire.” The Oka has a two-cylinder engine, which means that in case of problems it will be “alone”, but out of habit they talk about tripling.
Now four-cylinder engines are installed en masse in VAZ and GAZ cars. Everything matches here. When they say that a Gazelle engine is tripping, it means that three out of four cylinders are functioning. It’s the same with Ladas – the name of the fault can be taken literally.
Signs of a problem
When the engine starts to stall, the driver feels it based on a number of signs:
- strong vibration at idle,
- drop in engine power,
- Difficulty starting a cold engine.
If you experience any of these symptoms, there is likely a problem with one of your vehicle's cylinders. Or the problem is general, but in one cylinder it manifests itself clearly. What to do in such cases? Let's figure out why the engine is tripping, then it will become clear how to deal with this malfunction.
Let’s be clear right away - the engine can stall when cold, at idle, or in any operating mode. Why might a cylinder refuse to work? In fact, there are only three options: either there is nothing to burn, or there is nothing to ignite (for gasoline internal combustion engines), or there is not enough oxidizer (low compression). Therefore, when the engine stalls, the reasons must be sought either in the fuel supply, or in the generation of a spark, or in low compression (especially for diesel engines).
If the engine starts to stall, you should immediately troubleshoot the problem. Otherwise, you will get accelerated engine wear, increased fuel consumption and the possibility of a major accident at any time. This is due to the fact that fuel may continue to flow into the idle cylinder. It washes away the oil from the walls of this cylinder and dilutes the oil in the crankcase, which leads to increased wear, scuffing, and in extreme cases, an explosion of fuel vapors can occur.
Symptoms of breakdown
Typically, drivers learn about the problems under consideration by the characteristic sound of the engine, the sound of the exhaust and the resulting vibrations. In addition, the “CheckEngin” indicator lights up on the dashboard.
The following can also be used to determine engine tripping:
- unstable idle speed;
- drop in power indicators;
- increased fuel consumption;
- vibrations of the body and/or engine block.
Here you need to take into account that such symptoms can also indicate other malfunctions, and therefore an integrated approach to identifying the cause is needed.
Engine diagnostics
First you need to find the non-functioning cylinder. There is a simple and clear way for gasoline engines. At idle speed, it is necessary to disconnect the high voltage wires one by one, supplying a discharge to the spark plug. When the electrical supply is cut off at the working cylinder, the engine starts to rev harder. If the non-working one is turned off, there will be no changes in the operation of the motor. Care should be taken to avoid receiving a harmless but painful electric shock.
When the VAZ direct injection injector of the engine is damaged, the search for a non-functioning cylinder is simplified. There is no need to climb into the wires and risk getting an electric shock. It is enough to turn off the control of the injectors one by one. You also need to find a cylinder that, when turned off, does not change the behavior of the power unit.
When diagnosing a diesel engine, you need to turn off the fuel supply one by one. For example, you can simply unscrew the fuel line nuts. The goal is the same - to find a cylinder, when turned off, the engine runs without changes.
How to determine a bad cylinder
When carrying out repairs, it is very important to identify the problematic cylinder. There is a proven method for this, which is used by many automotive specialists. It involves removing the armor wires from the spark plugs one by one. The procedure for determining an inoperative cylinder consists of the following steps:
- Find a dielectric base to stand on during the procedure. This can be a thick rubber mat or a wooden board.
- Start the engine, and then keep the speed around 1500.
- Take the wire itself (not the cap) and disconnect it from the spark plug. If the sound of the engine has changed, then the cylinder is working.
- Reinstall the wire and then follow the previous step for the rest. If the engine sound does not change when disconnected, then you have found a faulty cylinder.
Finding the reason
Having found out which cylinder is causing the engine of a VAZ or a car of another brand to fail, we proceed to further research. You need to remove the spark plug and inspect it for the presence of gasoline. If the contacts are wet, it means either there is no spark, or the mixture is excessively rich or, on the contrary, lean.
If the candle is to blame
Install a known good spark plug and check the operation of the cylinder. If it starts working, you need to change the spark plug; if it doesn’t work, then the reason why the engine is throbbing is something else. We continue to search.
Problems with wiring or ignition distributor
The next thing to look at when there is no spark is the high voltage wiring. It is necessary to check the condition of the contacts and insulation. Are the terminals intact, free of corrosion, and is the insulation free of cracks? So the problem is elsewhere. Is there any damage? Replace the cable and check the performance of the spark plug again.
There is an express way to check high-voltage wires. It is necessary to start the engine, which has started to stall, in the dark - at night or in a windowless box with the lights off. Under such conditions, all breakdowns will be clearly visible in the form of sparks. With such a malfunction, the voltage simply does not reach the spark plug, so it does not spark.
If the wiring is OK, inspect the distributor cap. Due to a malfunction of this device, different cylinders work intermittently in turn. Cracks on the cover are a clear sign that one of the contacts in the ignition distributor has burnt out, so the engine began to stall.
Air intake from outside
If the spark plug is working properly and the discharge is supplied to it as normal, then the problem is in the air-fuel mixture. Sometimes the intake of air from outside dilutes the injection of gasoline to a concentration at which the mixture does not ignite.
The reasons for air getting into the cylinder can be very different: from damage to the intake manifold pipe to depressurization of the cylinder head seals. This is manifested by the fact that the engine stalls at speed and stalls when the load increases.
To fix the problem, you need to replace the damaged duct or seals. It is possible that air is leaking through the cylinder head gasket. You can replace the gasket yourself or contact a specialist.
Insufficient compression
Sometimes compression in the combustion chamber does not reach the desired value due to loss of tightness. If the mixture is not compressed to the desired level, the concentration of gasoline vapor is insufficient to ignite. Often the cause is stuck piston rings.
Due to accumulated deposits, the rings “stick” to the piston grooves and do not provide proper tightness. During the compression stroke, the air-fuel mixture seeps through the gaps of the piston-cylinder pair. Compression drops, fuel does not ignite.
In diesel engines, fuel spontaneously ignites due to high temperature when air is compressed. And if the compression is insufficient, then there will be no ignition. The quality of fuel atomization is also important here. If the high pressure fuel pump or injectors do not meet the specified parameters, then the fuel will not be evenly distributed in the combustion chamber in thin droplets, but will be “poured” or injected in large droplets. Such a spray of fuel, even with good compression, can lead to cylinder failure.
If the air duct is in good condition, but signs of malfunction have recently appeared, use Suprotec Active Plus tribological compound. It is added to motor oil. In terms of its mode of action, it is an engine additive; it does not change the composition of the lubricant and does not react with its components.
Engine oil additive "Suprotek Active Plus"
Restores compression, reduces fuel consumption and oil waste, reduces wear rate and extends the life of internal combustion engines of any type. Facilitates cold starts and protects against overheating in traffic jams.
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The Suprotek Active Plus product improves the operation of valves and the oil pump by removing contaminants from friction pairs. The product also restores worn parts of the cylinder-piston group at a microscopic level. The tribo composition is capable of decoking stuck piston rings if the case is not completely advanced.
This set of factors helps restore compression in the combustion chamber to nominal values. The gaps in the friction pairs are normalized, and a thicker film of lubricant is retained on the parts. The cylinder operation returns to normal.
Of course, in advanced cases, when there is already wear on the inner surface of the cylinder, the additive will not help. This problem can only be solved by overhauling the engine with boring the cylinder and installing oversize pistons or lining.
To maintain in good condition and restore the characteristics of the fuel equipment of a diesel engine, it is recommended to use the Suprotek TNVD fuel additive.
Fuel additive "Suprotek TNVD"
Additive for high-pressure fuel pumps of diesel engines of any design (in-line, distribution, main in Common rail systems)
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Suprotek MAX injection pump additive for trucks
For injection pumps of diesel internal combustion engines of trucks and special equipment: in-line, distribution, main fuel pumps, COMMON RAIL systems, PUMP-NOZZLE systems.
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Replacing spark plugs yourself
Of all the above problems, faulty spark plugs are the most common. Therefore, we will look at this problem in more detail.
Spark plugs must be replaced according to the established period, since only in this case can reliable and stable operation of the engine be ensured. As a rule, spark plugs are replaced after the car has traveled more than 20,000 kilometers (each brand has its own deadline), however, if the engine starts to trip, this element must be replaced before the established period.
Replacing spark plugs can be divided into the following stages:
- Before starting work, you need to clear the engine compartment of debris and dirt, since foreign elements cannot enter the cylinders.
- We remove the engine elements in order to gain unhindered access to the spark plugs. In some cases, it is almost impossible to remove all the elements for unhindered access to the spark plugs, since a huge number of elements will need to be disassembled. In order to remove the spark plugs in this case, you need to use special extensions and adapters. It is worth noting that before starting work you need to wait until the motor has completely cooled down, as you can get burned while doing it.
- We unscrew the spark plugs one by one, disconnecting the high-voltage wires. At the same time, we note that in order to prevent an accident, you must first remove the battery from the car, since in some cases, due to certain malfunctions, electricity may be supplied even when the ignition is turned off. When unscrewing, you need to monitor the force applied, because if the spark plug does not budge, it is better to have similar work done at a car service center. This is due to the fact that if the spark plug cannot be unscrewed, then there is a possibility of the thread breaking.
- To prevent debris from getting into the resulting holes, you need to cover them for a while.
- At the first stage, the spark plugs are screwed in using your hands, and then they are tightened using a special mechanism that allows you to measure the amount of force applied (in the absence of such a mechanism, the spark plug is screwed in another ¾ of a turn). High voltage wires are connected.
- Engine operation is checked.
- All elements are collected in reverse order.
To ensure stable engine operation, spark plugs must be replaced periodically. As can be seen from the above stages of carrying out such work, it can be done independently without the use of special tools.
- Do-it-yourself engine diagnostics
- Self-unloading of the engine
- Installing a Lada Priora engine on a VAZ 2115-13
- Chip tuning of VAZ 2110 engine
When an injection engine fails
It is much more difficult to determine the cause of the malfunction if the engine with an injector is malfunctioning. Power units of this type are equipped with electronic systems that the uninitiated should not meddle with. The maximum that can be done is to check the condition of the spark plugs and injectors.
We have already covered how to check the ignition. With injectors the algorithm is approximately the same. We replace the nozzle of the non-working cylinder with a known good one. If it works, great.
For example, often due to this malfunction, the Kalina engine, a generally unpretentious power unit, fails. Replacing the injectors helps solve the problem. However, it is better not to bring the engine to this state. At the first sign of leakage, add SGA flush from Suprotec to the gas tank.
Detergent additive for gasoline "SGA (SGA)"
Cleans and lubricates fuel pumps and injectors, extends their service life. Improves injection, which reduces fuel consumption and increases dynamics. Suitable for any petrol systems, including TFSI, TSI, GDI, MDI.
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This mild additive flushes the injectors and protects them from corrosion and wear. The product also improves the operation of the fuel pump, valves and other moving parts of the fuel supply system. When used systematically, flushing "Suprotek SGA" significantly increases engine life.
If even after washing the check light is on, the engine is running, and no improvements are noticeable, then the nozzle already requires replacement. No additive will help, you need to change the nozzle. This is more expensive and takes more time than pouring an additive into the gas tank, so we recommend systematically engaging in prevention.
Eliminating tripping
Having made a diagnosis and established a “diagnosis”, they begin to correct the situation. When the problem is in the wiring or spark plugs, it can be easily fixed by replacing the faulty elements. Accordingly, they come with the switch, as well as ignition coils. If both the fuel and air systems are clogged, you will have to tinker a lot. The injectors are washed with special solutions, and the oxygen sensor, which is not functioning correctly, is replaced. If, after washing the injectors, fuel still fills the spark plug, they are replaced with new ones. The same should be done with the remaining elements that make up the fuel system, the failure of which causes the engine to trip.
If the engine stalls when cold
It happens that the engine stalls when cold only in wet weather. Having warmed up to normal temperature, the engine begins to operate normally. This is a clear sign that the insulation of one of the high-voltage wires is damaged. Due to dampness, electricity breaks through to the ground, the candle cannot produce a spark. When the engine warms up and dries, the leak bridge disappears and the engine runs normally. There is only one solution - change the high voltage wires. How to determine which of them is damaged was discussed above.
Air supply failure
Improper air supply at the intake also leads to intense engine vibration. In this case, the risk of depressurization increases, due to which the power plant will suck in excess air, reducing overall power and stability.
To check the air system, you need to shut off the inlet pipe near the air filter and start pumping air to ensure the required pressure (usually it is 0.5 atmospheres). Then you should start looking for the leak. If there is no pressure drop, it means the system is fully operational. If there are hissing sounds in any place, the unit will most likely need to be repaired.
As for the lack of supply air, it is often caused by filter contamination , due to which it has lost its throughput. Fixing the problem is very simple: first of all, you need to remove the filter, and then check how the engine works without it. In addition, the problem also appears when the throttle valve becomes clogged. Such an element requires careful diagnostics and testing, so they must be performed at every scheduled technical inspection, along with changing the oil, filters and other operating elements.
Often, engine stalling is caused by a damaged TPS, mass air flow sensor or other sensor that sends an incorrect signal to the electronic control unit. As a result, the last unit cannot determine how open the damper is and how much air mass has entered the motor. As a result, the remaining components of the power plant are not able to correctly calculate the composition of the fuel-air mixture, which entails additional problems.
To verify that the sensors are faulty, you need to check the operating mode with a scanner installed in the diagnostic connector, and then compare the received data with the nominal ones. Any deviations from the norm lead to the beginning of the engine tripping.
If the engine stalls at idle
Are there any special reasons when the engine idles at idle? More likely no than yes. At idle, the engine may stall for any of the reasons discussed in this article. It makes no difference whether the problem is with a Peugeot, Kalina or a car of another brand. The algorithm for finding the causes of the malfunction is the same. If the engine revs only at low speeds, then a slight burnout of the valve is possible. At high speeds, the mixture or air does not have time to pass through the burnout, compression rises and the cylinder begins to work. This diagnosis is verified by examining the exhaust pipe. If oil flies out of it, then the valve is definitely burned out.
Incorrect operation of injectors
If your car has distributed or direct injection, then the cause of the engine tripping may be a malfunctioning fuel injector. It may overflow or not inject gasoline into the intake manifold or directly into the combustion chamber.
You can check the performance of the injectors at the stand. In the garage - just swap them and watch the scanner readings for errors.
A stand for testing the performance of fuel injectors when searching for the causes of engine tripping
A stand for testing the performance of fuel injectors when searching for the causes of engine tripping
