Why can a VAZ 2115 engine have problems with an 8-valve injector?

Causes of malfunction

Before we begin to analyze the issue, it is worth understanding that the power unit requires certain components in order to function. An engine requires four components to run properly: air, fuel, spark and functioning electronics.

Based on this, you can determine exactly where the fault may be hidden and identify the main components. The VAZ 2115 engine is having problems with the 8-valve injector, where to look for the reasons:

• Sensors and ECU.
• Fuel, as well as its supply components.
• Air.
• Sparking.

conclusions

The design of the 8-valve injection engine VAZ-2114 is quite similar to the first generations of this engine - “Samara”. Of course, the designers made many changes to the features of the power unit, but in many ways they remained similar. Repair and maintenance of this engine must be carried out regularly, which will also reduce wear on the parts located inside.

Many motorists have encountered problems with the engine of a VAZ 2115. The reason, as in all cases, is the formation of an air-fuel mixture or the lack of a spark in one of the cylinders. This article will tell you how to fix this problem.

Elimination methods

To correctly find the problem and fix it, the motorist should have knowledge of the design of the engine and its systems, as well as have the tools. A very indispensable element is time and hands growing from the right place. So, now you can begin to analyze the processes aimed at troubleshooting the problem.

Sensors and ECU

Many car repair mechanics recommend checking the software and meters, of which there are quite a lot in modern cars, before getting into the mechanical part.

So, first you should connect to the electronic engine control unit and carry out diagnostics using special software. The vehicle owner will need a USB-car cable, called K-line or OBD II, a tablet and the appropriate software.

After connecting and identifying the automotive equipment, it is worth carrying out diagnostic operations. If a software failure is detected, it must be removed and the system restored to functionality.

Also, the diagnostics will show which of the sensors has lost its functionality.

Which sensors are responsible for the normal operation of the engine, and their failure can lead to tripling of the power unit:

• Idle speed regulator. If this meter fails, then the engine will run cold. In this case, the engine will not only stall, but also have difficulty starting.
• Mass air flow sensor. Quite an expensive part in any car. Often, it does not fail, but the measuring grid becomes clogged. To restore operation, you need to clean the mesh.
• Crankshaft position sensor. It measures the number of engine revolutions, thereby regulating the supply of the amount of fuel mixture.
• The coolant temperature sensor affects the operation of the system indirectly, but can affect and create artificial tripping.

Fuel and its supply components

An integral element in the formation of the air-fuel mixture is fuel. So, not enough of it leads to the formation of a lean mixture, but too much of it leads to a rich mixture, which can flood the system.

The first thing you need to start diagnosing is the pump and filter. Clogged elements can lead to insufficient fuel reaching the injectors. The gasoline pump is located under the rear sofa, where it is quite easy to reach, but the filter element is mounted on the bottom behind the right rear wheel.

An injector is a fuel element that sprays fuel. The clogging of this unit affects the amount of fuel injected into the combustion chambers. Therefore, it is necessary to carry out diagnostics quite often. This is done using a special stand. If necessary, it is worth replacing the elements.

Air

Air supply elements are quite important because they directly affect the formation of the air-fuel mixture. So, a clogged throttle valve or its jamming will cause the car to suffocate, which will lead to the effect of tripping or it will stall. To clean this unit, it is necessary to dismantle the entire throttle valve. The part is cleaned using carburetor cleaning fluid.

An important element is the air filter. If it has not been changed for a long time or it is clogged ahead of time, then a tripping effect may be created. To eliminate the malfunction, you need to replace the dirty part with a clean new element.

Sparking

The last component that is involved in the normal operation of the engine is the spark generator. This unit includes: spark plugs and high-voltage wires.

Defeated tripping at idle

For the sake of decency, I read all sorts of forums, but didn’t find anything sensible about my problem. Everyone changes everything as one, but the problem does not go away.

By the way, when driving the car behaves adequately, a little worse than before, but at idle it’s an ambush. I noticed that when I released the gas, the revolutions dropped very quickly by 800, sometimes by 500, and then leveled off again at 800. The XX revolutions did not float, they stayed almost rooted to the spot, and the engine was unstable like a child. I brought the laptop into the car, connected, looked at the parameters, in principle everything was normal, maybe the IAC had a few steps, but not critical. The injection time correction coefficient was 0.984, the injection time itself was approximately 2-2.5 ms, that is, normal for simultaneous injection. The UOZ was jumping, well, that goes without saying, the engine is churning, so it jumps.

The simplest thing was of course also done, I unscrewed the spark plugs, they were all in good condition, no oil, no gasoline, no carbon deposits. I also grounded all the explosive wires, all the sparks are strong, and all the boilers are working. I took off the timing case, the marks are in place, the 20th tooth of the generator pulley opposite the crankshaft sensor, everything is as it should be. I was already upset, thinking that either some valve was burning out, or the gasket between the cylinders had broken. With these thoughts I finished the renovation. The next day I went to the store and finally bought myself a compression gauge, I had been wanting it for a long time, and then the opportunity came up.

I measured the compression, it certainly made me happy and sad at the same time: it was 12-11-11-10. When the outside temperature reaches +20, I’ll start adjusting the valves, they seem to be tight. Well, since the compression is non-zero and more than 10, then the valve is clearly not burned out and the gasket is intact. I breathed a sigh of relief) By the way, if you, like me, are a single repairman, then it’s easy to measure the compression alone) Warm up to operating temperature, unscrew the spark plugs, do something like this with the throttle

We remove the chips from the injectors and the ignition module and most importantly: the red wire, which is also positive, fits into the starter solenoid relay, replace that wire with something like this

Well, then we screw in the compression gauge and connect this wire to the battery positive, the starter turns successfully, the spark plugs and injectors are silent and we calmly take readings.

Let's move on, the problem remains as it is. The search continued. I removed the IAC, there was little soot, I blew it all off with a carb cleaner and stuck it in place. Zero effect as expected. Then, with the engine running, he put his head almost on the valve cover, abstracted himself from the tractor sounds, and thought he heard a subtle hiss.

Let me remind you that the injection time correction coefficient is 0.984, which doesn’t look like air leaks at all. Well, out of desperation, I took the same carb cleaner and started spraying it. The VUT valve is ok, but the injectors are not at all ok. 3 of the 4 injectors quickly sucked in the cleaner through the rings on the manifold and dried out almost instantly, only one remained wet, and the sound of the engine did not change at all. It’s already warmer) Although I changed the rings a year and a half ago.

I went to the store and bought new ones, better than last time. Balakovsky ones with graphite coating) This made me happy) Well, then everything is simple, we take out the ramp, I didn’t take a photo of this thing, my hands were all dirty and covered in gasoline. Naturally, the ramp with nozzles came out very easily. After analysis, the verdict: the upper rings are good, soft, the lower ones became stiff after a year and a half. Before reinstalling, I washed the injectors just in case, since I removed them. This is such a stray.

The syringe has 5 cubes, without a ring, the nozzle fits well with a little tension, there is enough pressure. The forces were clean, they became even cleaner) Then I put the whole thing back together, started it and received the long-awaited satisfaction of my successful work. In total, I bought a compression gauge for 500 rubles and a carburetor cleaner with rings for 170 rubles and not a single sensor. Thank you all for your attention and don’t rush to change everything, the problem can be much smaller and cheaper. If only I could find her.

Why does the VAZ-2115 engine troit, the 8-valve injector

If one of the cylinders completely refuses to work and the engine stalls, then during its operation you can hear the indignant grumbling of the engine.
“Boo-boo-boo” means it’s time to see a specialist. Moreover, you should not postpone this visit, since the wear of the motor in this case will be much stronger than during normal operation. If the engine stalls, its compression is significantly reduced, and all the necessary conditions are present for scuffing to occur on the pistons and cylinders. In this case, the operating temperature of the engine increases significantly, and therefore it begins to overheat. Without fully understanding all the nuances, it may seem that identifying such a malfunction is quite easy. But it also happens that the engine works absolutely normally, does not overheat and still starts to stall. In this regard, we will try to tell you point by point how to correctly diagnose and what you should first pay attention to in order to determine the cause of the engine tripping.

Engine diagram and structure

General view of the engine

Before we begin to consider the issue of the engine design and description of the characteristics, it is necessary to consider the design of the components and parts that are located directly in the main power unit and outside.

Diagram and design of the Samara-2 engine

1 – generator drive pulley; 2 – oil pump; 3 – timing belt; 4 – toothed pulley of the coolant pump; 5 – front cover of the timing mechanism drive; 6 – tension roller; 7 – camshaft toothed pulley; 8 – rear cover of the camshaft drive; 9 – camshaft oil seal; 10 – cylinder head cover; 11 – camshaft; 12 – front cover of camshaft bearings; 13 – pusher; 14 – valve guide; 15 – oil separator mesh for the crankcase ventilation system; 16 – exhaust valve; 17 – inlet valve; 18 – rear cover of camshaft bearings; 19 – fuel pump; 20 – housing of auxiliary units; 21 – ignition distributor sensor; 22 – outlet pipe of the cooling jacket; 23 – cylinder head; 24 – spark plug; 25 – crankcase ventilation hose; 26 – flywheel; 27 – crankshaft rear oil seal holder; 28 – ; 29 – cylinder block; 30 – oil pan; 31 – oil level indicator (oil dipstick); 32 – crankshaft; 33 – piston; 34 – connecting rod cover; 35 – connecting rod; 36 – crankshaft main bearing cover; 37 – ; 38 – .

Also, it’s worth looking at a cross-section of the VAZ-2114 engine:

Cross section of the Samara engine

1 – oil pan drain plug; 2 – oil pan; 3 – ; 4 – coolant pump; 5 – exhaust manifold; 6 – intake manifold; 7 – carburetor; 8 – fuel pump; 9 – cylinder head cover; 10 – camshaft bearing cover; 11 – camshaft; 12 – crankcase ventilation hose; 13 – valve adjusting washer; 14 – pusher; 15 – valve cotters; 16 – valve springs; 17 – oil scraper cap; 18 – valve guide; 19 – valve; 20 – cylinder head; 21 – spark plug; 22 – piston; 23 – compression piston rings; 24 – ; 25 – piston pin; 26 – cylinder block; 27 – connecting rod; 28 – crankshaft; 29 – connecting rod cover; 30 – oil level indicator; 31 – oil pump receiver

Characteristics of an 8-valve engine

Many motorists remember how at the end of the 90s of the 20th century and the beginning of the 2000s, the VAZ 2108-09, which was also called “Samara,” was popular on the roads of the CIS. These cars became legendary in that era. Due to the high popularity, the AvtoVAZ plant decided to resume production of these models with some modifications.

VAZ-2114 engine under the hood

Firstly, the VAZ-2114 received a modified engine

. In essence, this is an injection version of the Samara. Although it received some features from modern engines. If we consider in more detail, the Samara-2 engine (this is the type installed on the VAZ-2114) is a mixture of two engine options into one: from the VAZ 2108 and VAZ 2110.

Many motorists liked the Samara-2 power unit and fell in love with it. The main indicator was ease of repair and inexpensive spare parts. Thus, the 8-valve engine has become the standard for “price-quality” indicator.

When the basic information has been reviewed, you can proceed directly to considering the characteristics of the motor.

Table of main characteristics of the Samara-2 engine 8 valves:

Disassembly and repair: basic facts

Therefore, let’s consider the main operations aimed at removing the engine from the car:

1. At the preliminary disassembly stage, it is necessary to remove coolant from the system.
2. Another point that should not be missed is turning off the power to the car. This is necessary in order not to short-circuit the system.
3. Disconnect the fuel system.
4. We dismantle the components that supply air to the engine.
5. Disconnect the throttle, as well as all remaining air pipes and cooling system pipes.
6. We dismantle the injection system and receiver.
7. We film completely.
8. Let's disassemble the gas distribution mechanism.
9. and a pump.
10. Now, you can dismantle the collector.
11. Remove the pan, oil filter and pump.
12. Disconnect the gearbox and remove the clutch. The gearbox can also be removed for convenience.
13. Remove the cylinder head.
14. We dismantle the power unit.
15. We carry out final disassembly.

A major overhaul of the power unit will require more in-depth knowledge of the design and operating principle of the engine, but if desired, every motorist is able to understand this and carry out these operations with his own hands.

It is worth noting that when diagnosing malfunctions, it is worth carefully and carefully inspecting each part for defects.

Spark plugs are to blame

Most likely, the cause of the engine tripping is the spark plugs. In order to verify this fact, you should unscrew the spark plug from the cylinder and carefully inspect it. If the engine is operating correctly, the color of the side electrode, as well as the insulator, will be quite light. A brown tint is also allowed. A spark plug in this condition should be fully functional. But if the carbon deposits on the candle turn out to be black, then it simply cannot be working. It is either enriched with fuel or filled with oil.

Due to carbon deposits formed on the spark plug, it may not work at all or only work occasionally. Both the first and second options interfere with the normal formation of a spark.

The reasons for the appearance of carbon deposits on candles may be:

• the car engine has been idling for a long time or has been warming up for a long time;
• there is reduced compression in the cylinder;
• valve timing is shifted or disturbed;
• the injector is not working correctly;
• The oxygen sensor is faulty.

Next, it is imperative to pay attention to the housing in which the spark plug itself is placed. It should be completely white, without black dots or stripes. If, nevertheless, stripes or dots are visible on the body, this indicates that the spark plug is breaking through normally, but will not work.

But if, after inspecting the spark plug housing, nothing of the kind was found, you should check the spark while cranking the starter. To do this, a spark is inserted into the tip of a high-voltage wire and placed on the engine ground. The engine is cranked by the starter. At this time, you need to see if a spark jumps between the two electrodes of the spark plug. If it is visible to the naked eye and has a pronounced blue color, the candle is working correctly.

Replacement, performance check

For ease of access to the DS, it is better to drive the car into a pit or overpass, since it is easier to reach it from below. The only tools you need are 21 (22) and 10 keys, as well as a flat-head screwdriver.

You need to unscrew the DS counterclockwise. Since the sensor body is plastic, it can often be unscrewed by hand, but you may need to slightly loosen the fastening with a 21 (22) key.

We screw a new DS in place of the removed one, making sure that its pin fits into the hole in the actuator rod.

There is no need to tighten it with a wrench so as not to break the plastic thread; hand force is enough.

Sometimes problems with the operation of the sensor are not related to it, but to the drive. The fact is that some models use a plastic drive rod gear, and often its teeth “lick” themselves.

Therefore, when replacing the DS, it would not be superfluous to check the condition of the drive. To do this, after removing the sensor, you need to unscrew the drive mounting nut with a 10 mm wrench and carefully remove it, prying it slightly with a screwdriver.

It is important to ensure that the shock does not jump out and get inside the box.

After making sure that everything is in order with the drive gear, we install everything in place. Then we check whether the gears are engaged.

To do this, we jack up one front wheel, turn on speed 4 and ask an assistant to turn it, while we ourselves check with our fingers whether the rod rotates.

After checking the drive, screw on the DS and connect the wiring. All that remains is to check whether the symptoms of the malfunction have disappeared.

To do this, you can start the engine and monitor the behavior of the speedometer needle and listen to whether the interruptions in the operation of the power plant at idle have disappeared.

And then we just go out onto the highway and look at the behavior of the needle and the engine while driving.

Or you can check everything by measuring the voltage at the terminals with a multimeter.

Inspection of high voltage ignition wires

If it turns out that the spark plugs are in perfect order, this most likely means that the problem lies in the high-voltage wires.
In order to test this theory, it is necessary to consider each wire separately. First of all, you should pay attention to the tip of the wire that is inserted into the spark plug. It should be completely monochromatic and not have any plaque on it. The presence of foreign scale on it indicates that for some time this high-voltage wire worked in extreme mode. If this problem is not corrected in time, the wire may subsequently break, which will lead to much more serious problems and costs.

Timing marks

If the camshafts are incorrectly aligned relative to the crankshaft

– the reason for the engine tripping. The opening and closing timing of the intake and exhaust valves will not coincide with the engine strokes.

For example, at TDC of the piston the valve may be closed, so a flash will occur not only in the cylinder, but in the intake or exhaust manifold, depending on which valve is not closed.

This may occur due to a stretched timing drive.

. As the chain or belt is used, it stretches. Therefore, the opening or closing angles may shift. This leads to engine tripping.

What to do

If you have checked everything: the spark plugs are in order, there is a spark everywhere, the quality of the mixture is at the right level, you need to check the timing marks. We look at the degree of belt tension. In the case of a chain, how “out” the tensioner is. If the marks are knocked down, then we set them as needed.

After troubleshooting, we fix the problem. If the motor stops running, the cause has been found and eliminated.

Injector malfunction

Trouble the VAZ-2115 engine? This may be due to faulty injectors. This happens if:

• the injector is faulty (this is quite rare);
• low-quality fuel is used;
• injectors require cleaning;
• The power or control circuits to the injector are shorted or completely broken.

If one of the sensors does not work, an error will appear on the dashboard, which will serve as a kind of scanner. But if the error does not appear, then the problem lies precisely in the mechanical part.

And it also happens that it is simply not possible to find the reason why the engine is tripping. In this case, it is necessary to use computer diagnostics of the car, after which the cause of the tripping will become completely clear. As a rule, a motor malfunction of this kind can only be detected by a specialist. Therefore, it is best to contact professional service centers. This will help save both time and your own money.

Source

Valve clearances

Many may argue that this cannot be the cause of tripling. But there was a case in my practice when a car arrived to us, without an ECU, an on-board computer with a carburetor - a VAZ 2107. The power unit was severely troubled only when “cold”. After warming up the engine ran smoothly.

All systems were checked and no comments were found. We were the same skeptics. But we still decided to check the gaps - the dipstick did not want to fit in. We set the correct gap, the engine began to run smoothly in any condition - cold, hot.

What to do

If the engine is not equipped with hydraulic compensators, then you need to check the thermal clearances of the valves. For the future, in such power units it is necessary to adjust the valves after 15-20 thousand mileage.

This is especially true for the use of HBO. In this case, you can get a burnt valve and repair the cylinder head.

In case of engine tripping, you need to check the thermal clearance of the valves. On VAZ 2107 engines, the gap is checked with a feeler gauge

Why troit 2115

What does “ TROIT” - this means that one of the cylinders is not working, in total there are 4 cylinders in the 2115 engine, when one of them fails, it turns out that only 3 cylinders are working, which is why they say that the engine is troiting. Sometimes it happens that two cylinders on a car stop working at once, then it turns out that the engine is running double, but no one says that, everyone says that the internal combustion engine is running triple.

There may be several reasons why the VAZ 2115 starts to triple and all of them, as a rule, are located in one place on the cylinder head.

The most common causes of VAZ 2115 engine tripping:

• Spark plug;
• High voltage wires;
• Ignition module;
• Crankshaft position sensor;
• Fuel injectors;
• Air leak;

Each of these parts or causes can seriously affect the performance of the engine and lead to the failure of one of the cylinders. Let's look at each of the reasons in more detail.

Spark plug

One of the most common reasons why a car starts to misfire is the spark plugs. According to the regulations, it is recommended to replace spark plugs no later than 30,000 km, which few people comply with, and sometimes they drive on spark plugs until they completely fail.

After prolonged use, spark plugs lose their properties, the gap between the electrodes increases, carbon deposits appear, the insulator cracks, etc. which leads to spark plug failure and, consequently, engine failure.

If the engine in your car starts to misfire, the first thing you need to do is replace the spark plugs with new ones; this will never be a bad thing, even if the reason is not them.

conclusions

The bottom line is that it can be emphasized that the following malfunctions may be the reasons for the VAZ 2115 engine to fail:

Spark plugs High voltage wires. Coarse fuel filter Burnt valve. Blown cylinder head gasket Injector Crankshaft sensor. Ignition module.

• Candles
• High voltage wires
• Coarse fuel filter
• Burnt valve
• Blown cylinder head gasket
• Nozzle
• Crankshaft sensor
• Ignition module

Having discovered any of them, the car owner needs to contact a service center, where specialists will accurately determine the nature of the breakdown and be able to fix it. If the VAZ 2115 engine is malfunctioning and you do not have the proper experience, then you should not carry out repairs yourself, this can lead to an even greater deterioration in the condition of the car or injury to the technician himself!

Content

As part of the renewal of the LADA Samara family, the Volzhsky Automobile Plant released the VAZ-2115 in 2000 as a replacement for the popular VAZ-21099 sedan. The model received a completely new front end with new optics, a roof of a different design, new front fenders, an improved interior and more reliable electrical equipment. In 2008, the VAZ-2115 underwent a small facelift to “refresh” the appearance of the car.

Production of this model was completely discontinued in 2012 - it was replaced by the more modern LADA Granta.