The situation when engine-troit motor-car Chevrolet NivaIt always catches the wearer by surprise and creates an emergency on the road, a condition characterized by unstable powertrain operation, loss of traction and the appearance of the characteristic rattling exhaust sound, most often the problem is that one of the cylinders stops working or malfunctions without burning the fuel-air mixture properly.
Owners of SUVs VAZ-2123 They are often exposed to this phenomenon, because operating conditions involve high engine loads, and ignoring the symptoms can lead to serious consequences, including failure of the catalytic converter or even major repairs to the engine. The first step when vibrations appear should be immediate stop and initial visual diagnosis..
In this article, we will take a look at all the possible causes of motor instability, from simple electrical problems to complex mechanical malfunctions. You will learn how to diagnose yourself, what tools you will need and when you will need to access the service, understanding the nature of the malfunction will save you time and money, avoiding buying unnecessary parts.
The main signs of unstable operation of the engine
And it's not just the sound that makes you know if the engine is running rough, but the car itself is reporting the problem by changing the dynamics of acceleration and idling behavior. Vibration of the body This is the first and most obvious symptom that is felt even through the steering wheel and pedals.
When driving under load, such as climbing uphill or accelerating sharply, power dips become critical. The car twitches and the rpm floats without driver intervention. Check Engine on the dashboard can light up immediately or start flashing, signaling ignition misses, which requires immediate attention.
Also worth noting is the exhaust system, which can be the characteristic sound of a "machine gun queue" or cotton from the silencer, and the color of the exhaust gas also changes: if black smoke comes out of the pipe, it indicates a re-enriched mixture, and if you hear the smell of unburned gasoline, then the fuel simply flies into the exhaust system.
- 🚗 Strong vibration of the body and steering wheel at idle speeds.
- 📉 A noticeable loss of power and jerk during acceleration.
- 🔊 Clapping in the muffler and changing the exhaust sound.
- 💡 Light or flashing lamp
Check Engine.
Diagnostics of the ignition system
The most common reason for the engine Chevrolet Niva Troit, there are malfunctions in the ignition system. VAZ-21214 an individual ignition coil is used for each cylinder, which simplifies the search for a defect, but requires a competent approach.
The first thing to do is check the spark plugs, the oil plaque, or the increased gap between the electrodes can prevent the formation of a quality spark. If the candle is black and wet, this is a sure sign that the gasoline in the cylinder is not burning, and it is also important to inspect the high-voltage wires (if you have them) for breakage.
⚠️ Attention: Check high-voltage wires and coils on the working engine is carried out extremely carefully, using dielectric gloves to avoid electric shock.
The ignition coils often fail due to overheating or aging insulation. A simple way of checking is to shift the suspicious coil to another cylinder. If the problem has moved with the coil after the reshuffle, the part is defective and needs to be replaced. Poor-quality candles or coils can cause the ignition module to fail.
☑️ Checking of the ignition system
Problems with the fuel system and nozzles
If the spark is all right, you should look for the reason in the supply of fuel. Nozzles. The uneven spray torch or the lack of gasoline supply can become polluted or completely fail over time, resulting in the impoverishment of the mixture in a particular cylinder.
A clogged fuel filter can also cause engine starvation, although it often affects all cylinders at once. However, if the filter has been changed for a long time and the tank has been mud, local clogs may occur in the gas pump mesh or the injector itself. The pressure in the fuel ramp must be normal, otherwise the ECU will not be able to correct the mixture.
The nozzle diagnostics use the exclusion method or the connection to a computer with the function of turning off the cylinders on the go. If the engine does not change when one of the nozzles is software-operated, then this cylinder did not work. Cleaning the nozzles on the ultrasonic stand often returns them to factory performance.
- 💧 Measurement of pressure in the fuel ramp with a manometer.
- 🔌 Checking the electrical resistance of the nozzles with a multimeter.
- 🧹 Washing the injector with a special liquid.
- 📟 Computer diagnostics of the power balance of cylinders.
Mechanical malfunctions and compression
The worst case scenario is mechanical damage to the engine, and if there's a spark and the fuel is supplied, but the cylinder is not working, then the leakage of the combustion chamber is broken, the test begins with a compression measurement, low cylinder pressure indicates wear of the piston rings, a burn of the valve or a breakdown of the gasket of the HBC.
The breakdown of the cylinder head is often accompanied by the departure of antifreeze and the appearance of a white emulsion on the oil probe, in which case the tosol enters the cylinder, causing a hydraulic shock or simply preventing the mixture from ignition.
How to measure compression correctly?
To measure accurately, the engine must be warmed to operating temperature (80-90 degrees), the throttle is fully open, and the battery is fully charged. Each cylinder is 4-5 scrolls with the starter, fixing the maximum value. The range of readings between the cylinders should not exceed 1 bar.
The valve mechanism also requires attention. Incorrectly exposed heat gaps (on engines without hydraulic compensators) or wear of hydraulic compensators can cause the valve to not close tightly, as a result, some of the compression goes away, and the cylinder stops working efficiently. Valve adjustment is a necessary procedure to maintain the health of the engine. Niva.
Impact of air suction and sensors
The internal combustion engine works on a precise balance of air and fuel, so if there's excess, unaccounted air in the system, the mixture becomes too poor, and ignition becomes impossible. Air suction It may occur through cracks in the intake manifold, through the nozzle nozzles or through the nozzle sealing rings.
Sensors play a key role in the formation of the mixture: a faulty oxygen sensor (lambda probe) or mass air flow sensor (AMRV) can transmit incorrect data to the electronic control unit, as a result, the ECU prepares a mixture of incorrect proportions, which causes tripping, especially in transient modes of operation.
| Sensor. | Symptom of malfunction | Impact on work |
|---|---|---|
| DMRV | Floating turnover, high flow | Wrong calculation of air mass |
| Lambda probe | Black candle-on-candle tan | Mixture correction error |
| DPC | Engine's dead, no spark. | Loss of synchronization |
| Throttle sensor | Pulls on gas press | Wrong load calculation |
The unaccounted air suction is one of the most difficult problems to find, because the visual cracks in the pipes are often not visible. Use the smoke generator to look for leaks.
Computer diagnostics and error codes
Modern car Chevrolet Niva It's equipped with a self-diagnosis system. OBD-IIYou can count error codes that will indicate the direction of the search. P0300 – P0304 indicate the omissions of ignition in specific cylinders.
But don't blindly trust the codes. The error can be a consequence, not a cause. For example, the lambda probe error code can come from the oxygen coming from a idle cylinder in the exhaust pipe, so you need to analyze a set of parameters: fuel correction, ignition angle and readings of all sensors in real time.
Sometimes, it helps to reset the ECU adaptations after repairs, so that the control unit can retrain and adjust the fuel cards to the new conditions, but if the problem is mechanical, no resets will help.
Remediation and prevention
Removing trim starts with a consistent check of systems, from simple candle replacement to complex engine defects, and if you find a faulty coil or candle, you better change them with a kit or pairs to avoid the problem reappearing soon.
Use high-quality fuels to prevent this, and periodically add proven injector cleaners to the tank. Watch the air filter condition, which also disrupts mixing, and regularly changing oil and antifreeze will prolong the life of the seals and prevent overheating.
⚠️ Attention: Long driving on the trembling engine is guaranteed to disable the catalytic converter due to the ingress of unburned fuel into the exhaust tract, where it burns out.
If you can't do it yourself, you can call the experts. Professional diagnostics with an oscilloscope allows you to see the shape of the ignition signal and the work of the nozzles in detail, which is not available to a regular scanner. Remember that timely repair is cheaper than replacing the engine.
When replacing candles, always use a dynamometer key. A retraction can damage the thread in the block head, and an undertraction can cause the candle to burn out and lose compression.
Frequently Asked Questions (FAQ)
Can I drive if the engine is too heavy?
You can only drive your own course to the nearest service or garage, and then with great care. Prolonged operation will lead to the destruction of the catalyst and damage to the piston group due to the washing of oil from the walls of the cylinder with gasoline.
Why does it only work on a cold engine?
This may indicate a malfunctioning temperature sensor, air suction (cold gaps are larger) or problems with nozzles that do not hold pressure after cooling, and problems with thermal gaps of the valves may also be possible.
Which candles are best to put on the Chevrolet Niva?
The best choice is considered to be original candles. AU17DVR or qualitative analogues of NGK and Bosch It's a potassium number of 17. It's important to keep the electrode gaps right.
How much does it cost to diagnose the causes of trivia?
The cost of computer diagnostics in the service varies from 500 to 1500 rubles. Full diagnosis with analysis and measurement of compression can cost more, depending on the region and level of service.