The situation when engine It starts to idle, which is familiar to many owners of this model, and the car starts to twitch, the tailpipe starts to hear the characteristic clapping, and the vibration of the body becomes so strong that it can't be ignored, most often it means that one of the four cylinders has stopped working or is not functioning correctly, burning fuel inefficiently.
This malfunction cannot be ignored, since unburned gasoline enters the catalyst and quickly disables it, and also washes oil from the cylinder walls, causing accelerated wear of the piston group. The owner needs to quickly identify the source of the problem, which can be hidden both in the ignition system and in the mechanical part of the engine.
In this article, we will discuss in detail the malfunction search algorithm, starting with the simplest and most likely causes, and end with complex diagnostic procedures. ESUD (Electronic Engine Control System) will help you save time and money on the service.
Primary Diagnostics: How to Find a Non-Working Cylinder
Before you buy new parts, you need to know exactly which cylinder is not working. The simplest and oldest method is to turn off the high-voltage wires on the engine running. However, this method requires extreme caution, since electric shock from the ignition coil can be quite unpleasant.
The modern approach involves the use of a motor tester or at least a simple program for a laptop connected via a computer. K-Line Adapter: By analyzing oscillograms or engine performance in real time, you can see the ignition gaps in a particular cylinder without risking discharge.
If you decide to act "old-fashioned" method, be sure to use dielectric gloves or put a tight rubber gasket on the wire. Remove the cap sharply but carefully so as not to damage the insulation of the wire, which is on the wire. VAZ 2114 It's often dry.
β οΈ Attention! When removing wires on a running engine, never touch the metal body or engine with your bare hands. The voltage in the secondary circuit can reach 25-30 kV, which is dangerous to health.
After determining the problem cylinder, the logic of the search narrows: if the first cylinder does not work, then the problem is localized in the elements related to it (candle, nozzle, valve), or it is a general malfunction (air sucking, low fuel pressure).
Ignition system: candles, wires and module
The most common reason why VAZ 2114 engine is troit (8 valves or 16) is in the ignition system. Ignition plugs are consumables, and their condition directly affects the quality of spark formation. Nagar, increased clearance between electrodes or a breakdown of the insulator lead to ignition failures.
High-voltage wires on these cars are prone to drying and cracking. In damp weather, through microcracks, the spark can "run away" to the mass, especially if the wires are on the engine. The check is best done at night, opening the hood, and the break will be visible as a blue glow.
The ignition module (or coil, depending on the year of manufacture and the type of ECU) also often fails, microcracks can occur inside it at soldering sites or a winding break, and if the replacement of candles and wires did not help, the module should be checked on another car or replaced with a known serviceable one.
When buying candles, pay attention to the kalyl number. For VAZ 2114 with an 8-valve engine, candles with a gap of 0.7-0.8 mm are optimal, and for a 16-valve one - 1.0-1.1 mm.
Remember that even a new candle can be defective. Before installation, it is recommended to check the spark by placing the candle on the mass of the engine (but not screwing into the cylinder so that the gasoline vapors do not flash inside) and scrolling the starter.
Valve adjustment and cylinder compression
If the electrical system is fine, we move to mechanics. 8-valve engines VAZ 2114 lacks a hydraulic compensator, which requires regular manual operation. heat-gap adjustment A tight exhaust valve is one of the main causes of triplication to hot.
When the valve does not close tightly due to the absence of a gap, the compression in the cylinder drops, and some of the gases break into the exhaust manifold, heating the plate of the valve, which leads to the burnout of the valve and, as a result, to a complete loss of tightness of the cylinder.
Checking compression is a mandatory stage of diagnosis. Measurement is made on a warm engine with a fully charged battery. The normal value for a healthy engine is 10-12 bar. The range of readings between the cylinders should not exceed 1 bar.
| Engine condition | Compression (bar) | Probable cause | Recommended action |
|---|---|---|---|
| Norma. | 10 - 12 | Missing. | Valve adjustment |
| Wearing rings | 6 - 8 | Rings in the rings | Rings removal or replacement |
| Laceration of the valve | 3 - 5 | Breaching of the seal | Valve replacement, laundry |
| Critical wear and tear | 0 - 2 | HBC gasket breakdown | Replacement of the HBC gasket |
There is a dry and wet method of checking compression, and if the compression increased dramatically after infusing 5-10 ml of oil into the cylinder, then the piston rings are worn out, and if the readings remain the same, the valves or the block head gasket are the problem.
Why is it important to adjust the valve on time?
The valve adjustments at VAZ 2114 should be done every 20 to 30 thousand kilometers. If the gap is too large, you hear a characteristic tsokot, which, although unpleasant, is less dangerous. If there is no gap (the valve is clamped), it does not have time to cool down, expands and rests on the saddle, losing its tightness. This is a direct route to expensive repairs of the HBC.
Fuel system and injectors
The engine may be unstable due to problems with fuel supply. nozzle If poured or conversely clogged, the mixture in the cylinder will either be too rich or too poor, leading to ignition misses.
Clogged injectors often cause tremors after prolonged parking or using poor-quality gasoline. Ultrasound cleaning or special washing for an injector can restore the spray torch and even out the engine.
Also worth paying attention to the pressure in the fuel ramp: if the fuel pressure regulator (RDT) is faulty and dumps the fuel back, or if the gas pump is clogged, the engine will lack fuel under load, although this may be less obvious on idlers.
- πΉ Check the resistance of the nozzle windings, it should be within 12-16 Ohms for high-omb VAZ nozzles.
- πΉListen to the injectors with a medical stethoscope or a long screwdriver β all should click rhythmically and evenly.
- πΉInspect the wiring harness for the injectors; corrosion on the connectors is a common issue on older VAZ 2114s.
Before removing the nozzles or filter, you need to relieve pressure by turning off the gas pump and producing the residues of gasoline.
Unrecorded air suction
One of the most insidious reasons why VAZ 2114 The air pump that goes into the intake manifold after the mass air flow sensor (MFR) depletes the mixture, and the ECU (Electronic Control Unit) tries to compensate by increasing the fuel supply, but it lacks the adjustments for the idle ones.
Most often, air is sucked through the receiver's sealing rings, cracks in the DMRV corrugator, or through the hose of the vacuum brake booster. You can find the place of the sucker by spraying the carburetor cleaner or "Fast Start" on the engine running.
If the engine speed changes (grows or falls) when liquid hits the area, it means that there is leakiness, and the pump can be diagnosed with a smoke generator that pumps smoke into the intake manifold and clearly shows the leakage sites.
βοΈ Finding the air sucker
Pay special attention to the condition of the gasket between the intake manifold and the cylinder head, which eventually tans and ceases to keep tightness, especially if the manifold often warmed and cooled.
Electronics: sensors and ECUs
You can't discount the electronic components. DMRV (Mass Airflow Sensor) can transmit incorrect data about the amount of incoming air, which leads to improper mixture, and you can check it by temporarily turning off the connector: if the engine performance has improved or remained the same, the sensor is likely dead.
The throttle position sensor (TPD) also affects idling, so if the sensing sensor gives off a surge voltage in the initial throttle position, the ECU can't stabilize the revs, and the engine starts to triple.
The ECU(s) on the VAZ 2114 (usually January 7.2 or Bosch M7.9.7) can also be a source of problems. Burning out of the nozzle key or ignition coil inside the control unit is not uncommon, especially after lighting or welding.
β οΈ Be sure to reset the bugs and adapts of the ECU before replacing any sensor. Sometimes the system continues to work according to the old, erroneous parameters, even if the malfunction is fixed.
For deep diagnostics of electronics, a scanner is needed that can read not only error codes, but also parameters in real time: fuel correction, ignition angle and voltage on the oxygen sensor.
Integrated approach: 80 percent of the time, trifles are caused by candles, wires, or air suction, and start with these simple elements before you sin on the ECU or the engine mechanics.
Frequently Asked Questions (FAQ)
Why does the VAZ 2114 engine only work on the cold?
This may be because there are more cold gaps in the valves, and if they're already broken, the tightness is lost, and the cold engine is running on an enriched mixture, and if one candle fails because of the soak, the cylinder doesn't work. Once warmed up, the sock is burned out, and the work stabilizes.
Could the catalyst be the cause of the trim?
Yes, if the catalyst ceramic cells collapsed and created backpressure in the exhaust system, or if they were completely clogged, the engine would "gasp." This is often accompanied by a loss of power and the characteristic noise of rolling ceramic balls under the bottom.
What is the best gasoline to pour so as not to trophy?
The VAZ 2114 is recommended to use AI-95 gasoline. Using AI-92 can cause detonation in some ECU modes, and AI-98 does not make sense due to the low compression ratio of the engine. The main thing is to refuel at proven gas stations, since bad gasoline is the No. 1 cause of failure of candles and catalysts.
How often should high-voltage wires be changed?
The life of quality wires is about 40-50 thousand km, but in practice they are changed to the state. If you see cracks on visual inspection, or you notice a "glow" in the dark, the wires should be changed immediately, even if they do not cause tremor right now.
Does the GRW belt affect the three-engine?
The belt itself doesn't directly affect, but if it's stretched or jumped on the tooth, the timing of the valves is disrupted, causing the valves to open and close in a bad time, the mixture to fail to burn efficiently, and the engine to start operating unstablely and triple.