Why the car won't start and what to do about it

Turning the ignition key, the driver observes the same picture every time. First, the instrument panel indicators light up to indicate the presence of fuel and battery charge. In the extreme position, the starter turns on and begins to rotate the crankshaft. To start a serviceable engine, a few crankshaft revolutions are enough, but what to do when the starter works, but the car stubbornly refuses to start? The culprit for this situation can be a variety of malfunctions, because the normal operation of the engine is ensured by several automotive systems at once.

Immobilizer enabled

What happens: the starter turns confidently, but the engine does not start.

After installing the alarm, control of the immobilizer passes to it. Sometimes, due to equipment failures or accidental presses on the key fob in your pocket, the anti-theft protection is activated. Depending on the circuit and the selected settings, the immobilizer blocks the fuel pump, injectors, ignition system or even the starter. In any case, the engine will not start.

What to do: if you accidentally turned on the lock yourself, then try to remove it by finding out the required combination in the instructions or on the Internet. In case of alarm errors, only its installer or a competent auto electrician can deal with the problem.

Low battery

What happens: the starter cranks the engine, but slowly. Dashboard lights dim or go dark.

Due to the low battery charge, the starter spins the engine insufficiently or with difficulty, and starting is out of the question. This happens after a long period of inactivity, especially in winter, when the problem is aggravated by thickened engine oil.

What to do: start the car by “lighting” it from a neighbor’s battery or in one of the other ways, and then charge or replace the battery.

Spark test

When the Check Engine light is on, the fuel pump is good, and the starter is working, the next thing to check is spark. To check it, you need to unscrew the spark plug, press it to ground and start the starter.

The check takes place one by one, on all cylinders. Such problems occur on many injection VAZ-2112 cars. The price of a new starter, by the way, is 2-3 thousand rubles.

Sources

https://drajver.ru/tehobsluzhivanie/vaz-2112-ne-zavoditsya-prichiny.html
https://autogearspb.ru/lada/vaz-2112-16-klapanov-ne-zavoditsya-prichiny.html
https://gil-service.ru/ts/vaz-2112-ne-zavoditsya.html
https://FokSevmash.ru/elektronika/ne-zavoditsya-vaz-2112-16-klapanov.html
https://zapchasti.expert/reshenie-problem/ne-zavoditsya/ne-zavoditsya-vaz-2112.html
https://delis-avto.ru/avto-ts/vaz-2112-16-ne-zavoditsya.html
https://FB.ru/article/288870/vaz—ne-zavoditsya-prichinyi-i-ih-ustranenie
https://www.vazzz.ru/pochemu-ne-zavoditsya-mashina-vaz-2112-inzhektor-16-klapanov/
https://peretyajka-salona.ru/prochee/pochemu-ne-zavoditsya-vaz-2112-inzhektor-16-klapanov-prichiny-i-foto.html

[collapse]

Fuel system malfunctions

What happens: the engine rotates, but shows no signs of life.

Without fuel supply to the cylinders, the engine naturally will not start. If there is gasoline in the tank, then most often the reason for the lack of fuel in the combustion chamber is a clogged filter, a non-working fuel pump or its relay.

Impurities in low-quality fuel clog the filter element mesh, and gasoline does not flow further. In winter, it can become clogged with frozen water. Because of this, due to increased load, the fuel pump sometimes fails. It can also break due to overheating when driving with an almost empty tank, since the pump is cooled by fuel.

What to do: you can only check on your own whether the fuel pump is working. Turn on the ignition and listen. If everything is normal, then a buzzing sound should appear in the rear seat area for 5-10 seconds. If the pump works but no fuel flows, it means its screen is clogged.

To clean or replace the filter or fuel pump, you will have to remove the seat cushion, open the hatch in the floor and remove the pump housing. If you don’t have car repair skills, it’s better to contact a service center.

Battery

The first thing you should look at is the battery. And it doesn’t matter whether we are talking about a hot injection engine or a cold one. It also doesn't matter at all how many valves it has. The batteries of all modifications of the VAZ model under consideration are of the same type.

To find out why the Lada does not want to start, open its hood and look at the battery indicator. If the latter is missing, measure the voltage with a tester - 11.5 volts will be normal. Lower readings indicate the need to charge. When this is not the reason, then look further. Be sure to check if the battery terminals are oxidized. If so, clean them with fine sandpaper.

Diesel freezing

This is the jelly that forms inside the filter / patch.com
What happens: the engine simply does not start.

Fuel that is not appropriate for the season in diesel cars thickens greatly in the cold. The paraffins included in its composition precipitate, clogging the fine filter and fuel lines. All this causes the engine to not start.

What to do: return the diesel to fluidity. To do this, you need to warm up the car in a warm garage or pour a special antigel additive into the tank. Afterwards, drain or use up the remaining summer fuel and refuel with winter fuel.

Sometimes you can get by with little blood and use a hairdryer to warm up just the fine filter under the hood.

Problems with the ignition system

What happens: the starter turns, but the engine doesn’t even catch.

In the absence of a spark, the fuel-air mixture does not ignite and, accordingly, the engine cannot start. The reasons lie in broken ignition coils or wires, as well as spark plugs with a layer of soot or a cracked insulator.

What to do: the easiest way is to unscrew the spark plugs and visually assess the condition of the electrodes: they should be clean and dry. Next, put on the spark plug, attach the spark plug thread to the metal part of the engine and turn it with the starter. If there is a spark, then everything is in order with the ignition. If not, you need to try other spark plugs, and then check the wires and coils, also replacing them with known good ones.

What you need to know about diagnostics

Simple advice: you don’t need to take your car to be scanned.
Due to the fact that laptops are now in almost every home, there are a lot of unscrupulous establishments where you can undergo such a check. When the program does not notice any errors, they tell you that there is nothing wrong with your car. By and large, this diagnosis can be called a simple pumping of money. A good diagnosis should proceed as follows:

• Errors are read first.

• The signals coming from the sensors on the injector are checked.

• The pressure created by the fuel is measured.

At the very end, you should receive the correct answer about what happened and what you have to do with the car in the future.

If a car enthusiast has an engineering streak, he can try to find the reason why the VAZ-2112 does not start. In this case, you can fix the problem yourself, saving on service costs.

Broken glow plugs

Hot spark plug tip / ScrewsNutsAndBolts YouTube channel
What's happening: The engine won't start and the spark plug light is on on the dashboard.

At low temperatures, fuel evaporates poorly, and without additional heating with glow plugs, diesel cars may simply not start. A malfunction is usually indicated by a constantly lit spiral indicator on the dashboard.

What to do: the spark plugs need to be removed, checked and faulty ones replaced. For the test, use a multimeter in dial mode. When the probes touch the central contact and the housing, a signal should sound.

You can also simply apply 12 V voltage from the battery to the spark plugs one by one. In 3–5 seconds, the electrode of a working spark plug should become red hot. The non-working one, accordingly, will remain dark.

A quick solution is to try to warm up the spark plugs several times and only then start the engine. They don't all fail at once, and if at least a couple works, that should help.

Sensor malfunctions

What happens: the starter turns, but the engine does not start. The Check Engine light is on on the dashboard.

All processes in the engine, including starting, are controlled in modern cars using an ECU. The “brains” read the readings of numerous sensors, and if any of them fails, the operation of the motor is disrupted or blocked. This is possible due to malfunctions of the crankshaft and camshaft position sensors, as well as idle speed, coolant temperature or detonation sensors.

What to do: identify and replace the defective unit. Unfortunately, only service specialists can do this. However, if you have an ELM327 scanner, you can try to find the problem yourself.

Options for developing situations

• Spark is present on the spark plugs of all cylinders. This is already a good sign. Let's proceed to the next point.

• There is a spark on the first and fourth cylinders, but no spark on the others. Conclusion: ignition coil 2112 does not work.

• There is a spark on the second and third cylinders, but no spark on the others. The conclusion is the same as in the previous paragraph. The ignition module should also be replaced. When after replacing this element the problem does not go away, the culprit is a malfunction of the output keys to the ignition module from the electronic control unit. Repairing the unit will solve this problem.

• When there are no sparks at all, the most likely reason may be a breakdown of the crankshaft position sensor, from which the commands for its formation come.

Violation of valve timing

What happens: the starter turns easily, but the engine does not respond at all.

Due to incorrect adjustment or untimely replacement, the timing belt or chain can stretch and jump several teeth, or even break completely.

This inevitably leads to a violation of the valve timing: the valves do not close at the right time, compression and ignition of the mixture does not occur. Depending on the design of the engine, the pistons may reach the valves and bend them, causing costly repairs.

What to do: check the timing marks. If necessary, install them in accordance with the vehicle's operating instructions. For the future: always change the belt or chain according to the regulations and adjust correctly.

Flywheel ring offset

What's happening: the starter turns idle, you can hear a creaking and squealing noise from under the hood.

The teeth with which the starter bendix engages are not made on the flywheel disk itself, but on a removable rim - a crown. It fits tightly when heated and sometimes, in rare cases, can turn. In this case, the starter regularly rotates the crown, but the flywheel itself and, accordingly, the engine do not spin up.

What to do: remove the starter, engage 4th-5th gear, and then, using a screwdriver to lock the crown, push the car forward or backward a little. If the engine rotates separately from the crown, then the latter needs to be removed and replaced with a new one. Possibly together with the flywheel. The procedure is quite complicated and is performed at a service station.

VAZ 2112 16 valve injector will not start

The starter device is considered one of the main mechanisms of the ignition system in any car, and domestically produced cars are no exception. If this unit breaks down, the driver simply will not be able to start the engine, and accordingly, full operation of the car will be impossible. For what reasons does the starter not turn in a VAZ 2112 and how to change this device if necessary - we will talk about this below.

Possible starter malfunctions: causes and symptoms

So, first, let's look at the faults that cause the starter to not turn on a VAZ 2112.

If the engine does not start, it does not mean that the problem lies in this particular device, so first you need to make sure that the problem does not lie in a discharged battery:

If, when trying to start the VAZ 2111 starter with the key, the crankshaft turns once or frequent clicks of the device are heard, this is indicative of a low battery. Also, the reason may be poor contact of the terminals with the battery or disconnection or poor contact of the mechanism ground.
If, when starting the engine with the key, you heard only one click, but the starter does not turn, and therefore the engine does not start, most likely the problem lies in burnt power contacts. In particular, we are talking about the retractor relay mechanism. Due to burning, these contacts will not be able to conduct voltage through them. It also happens that when starting the engine with the key on a VAZ 2112, the starter does not turn, but the contacts are intact; if this is the case, then the reason should be sought in the non-working electric motor of the mechanism or its drive.
The appearance of uncharacteristic noise during operation of the device may be due to wear of the bushings of the bearing devices. In addition, the reason may lie in the wear of the journals on the armature shaft.
It is necessary to check the quality of fastening of the device. It is quite possible that problems in its performance are due to loosening of the screws. It must be taken into account that vibrations can negatively affect the functionality of the mechanism.
The reason may also be damage to the drive teeth (the author of the video is the Lexin channel).

Final diagnostics of the starter before replacement

If the starter on a VAZ 2112 does not allow you to start the engine, before starting repairs, you should carry out a full diagnosis of the device. First, you will need to open the hood and dismantle the air filter element; to do this, unscrew the bolt on the body and use a screwdriver to loosen the clamp on the hose.

Which fuse is responsible for the emergency lights?

The VAZ 2112 starter itself is located directly under the air filter housing, the diagnostic procedure is carried out as follows:

First you need to check how well the wires connected to the mechanism are connected. There is a possibility that the problem lies in the electrical circuit.
If the wiring is intact, then turn on the optics. When the battery is discharged, the light from the flashlights will be quite weak.
Remove the wires from the ignition switch connectors, and then connect them to each other (wires 30 and 50 in accordance with the car diagram). When the contacts are closed for a short time, the mechanism will begin to rotate; if this is the case, then the reason lies in the ignition switch.
When the lock is working, an additional wire is connected to the connector and relay, as well as to the positive terminal of the battery. If the starter unit works, this may indicate a problem in the circuit from the battery to the relay.
If these actions did not help identify the malfunction, then you will have to dismantle the unit and check it in more detail (the author of the video is Avtoelektika HF).

DIY mechanism repair and replacement

If the power unit does not start, it is necessary to repair the VAZ starter.

This procedure looks like this:

First of all, you should disconnect the battery, and then disconnect the wires connected to the traction relay.
Using a 13mm wrench, you will need to unscrew the nut that secures the positive contact of the cable connected from the battery to the starter assembly. The wire itself can then be dismantled.
Next, you will need to unscrew the nuts that secure the mechanism to the clutch housing. To unscrew the nuts you will need a 15mm wrench.
After completing these steps, the starter assembly can be removed. If you plan to replace it with a new one, then the replacement can be done at this stage. When replacing, you need to take into account the location of the wires connected to the starter; under no circumstances should they be mixed up. Therefore, before disconnecting the wires, it is advisable to mark them. If you do not want to change the mechanism, but plan to repair it, then you can start disassembling it.
To disassemble, you will need a 10mm wrench; you can use it to unscrew the nut located on the relay and remove the wire connected to the starter.
The relay screws that secure it to the starter assembly must be unscrewed using a size 8 wrench. Having done this, you can dismantle the relay.
After removing the relay, you can see the gasket, which is located between the front cover of the mechanism and the relay itself. It should also be removed for disassembly, but when dismantling it is worth paying attention to its condition. If you see that the sealing element is worn out and its quality is quite low, then it is better to replace this component.
When the seal is dismantled, it will be necessary to remove the spring, as well as the anchor.
The next step is to remove the parking stud nuts.
After completing these steps, you can dismantle the mechanism from the studs with the anchor itself. After this, it is necessary to thoroughly clean the internal parts and components of the device. For proper repairs, you should diagnose the contacts, and also completely disassemble the brush assembly and check its condition. In general, the procedure for repairing a mechanism is quite complicated, so not every car enthusiast chooses this method - sometimes it is easier to simply replace the unit with a new one. In particular, this will be necessary if the repair process did not produce any results.

Also, in addition to all of the above, it would not be amiss to check the functionality of the car alarm, since it is often to blame for such symptoms. If the alarm system malfunctions, it can block the engine starting system at its level.

Fuel system

The fuel pump strainer could be clogged and the fuel pump will not be able to produce the required pressure!

When operating the fuel system, we pay attention to the general condition and the presence of pressure in it. First of all, we check the pressure in the injector ramp; this is very simple to do: just slightly open the special black plug at the end of the ramp, and if there is pressure, you will immediately know about it.

Installation of triangular levers on Priora

Diagnostics can be carried out with a screwdriver or something similar.

Ignition system

The ignition system on the VAZ-2112 includes: battery, ignition switch, spark plugs, high-voltage wires, ignition coils, crankshaft position sensor. But more about everything.

We check the battery for sufficient power, integrity and clean contacts. Moving on to the ignition switch, we inspect it for visible damage, frayed and melted wires.
It happens that the contact group in the ignition switch fails (roughly speaking, it simply burns out), which does not allow the wires to close properly and start the engine.

For diagnostics, the lock must be disassembled or replaced with a new one.
The coils were removed for diagnostics, some of them are for replacement, punctures are visible
To dismantle it, just disconnect the power supply and remove it from the place of fixation.