If the car does not start, you need to immediately determine the reasons that negatively affect the starting of the engine. And for this it is necessary to systematize and reduce the number of variants of engine operation problems. Does the motor run with problems "cold" or "hot"? Does the engine run on gasoline or diesel? Answering these questions will help reduce the causes of poor engine performance.

Why does the engine start badly? You need to understand the root cause!

With half a turn it is possible to start only perfectly tuned types of engines with a carburetor or mechanical injection of the first generations, which do not have any electronics in their composition. In all other cases, the engine control unit must interrogate the sensors and, after analyzing their signals, give a command to supply a spark.

This takes several turns of the engine with the starter. In case of malfunctions, the process is delayed, which greatly irritates the owner of the car. In such cases, there is a problem with starting the vehicle. It is necessary to separate the factors that negatively affect the start of a gasoline and diesel engine.

Gasoline engine starts poorly

A gasoline engine differs from a diesel engine primarily in the presence of spark plugs. Not to be confused with glow plugs. That is, in order for the gasoline engine to work as expected, it is necessary to ignite the fuel-air mixture with a spark from a spark plug.

Why won't the car start "cold"?

The main reasons why a car does not start well when cold are:

Weak dead battery

This factor of poor engine starting is widespread! Frost leads to an accelerated discharge of the batteries.

• it is possible to start the vehicle by replacing the battery with a charged one, or to charge the existing one;
• if the automaker allows it, then you can "light a car". In this case, it is imperative to take into account the sequence of actions specified in the operating instructions.

Advice! If you are in doubt whether the vehicle will start up in frost due to a "dead" battery, then you should understand that the battery will have the strongest charge only at the first attempt to start the engine. From the moment the machine is opened with the “key fob”, processes that consume electricity are launched in the system, so it is important to act quickly!

The most likely to start a vehicle with a dead battery is:

1. Standing next to the car, open it and immediately sit in the driver's seat, turning on the ignition.
2. Wait 2-4 seconds to activate all vehicle systems.
3. Turn the ignition key further by activating the starter and starting the engine.

Low sparking

The second, frequent case is a low level of sparking.

This can happen for the following reasons:

• if spark plugs fail;
• in case of violation of the electrical connections of the ignition system;
• in case of failure of the ignition coils

In this case, it is necessary to identify the causes and eliminate the source of the malfunction that prevents the vehicle from starting with a cold engine.

It is enough to replace the spark plugs and check all the connections of the ignition system.

Reasons for poor hot start

For a novice car enthusiast, a difficult hot start looks like something supernatural. Why does the engine start badly? Literally half an hour ago I started the car from a half-turn, the hot engine is provided, and now the car will not start! Miracles, and nothing more. No magic - banal mechanics and physics. If the car does not start up hot, then the reason may be a malfunction of a sensor. Improper operation of one sensor can result in engine failure as a whole.

When carrying out maintenance, it is necessary to check the operability and condition of the sensors. Their incorrect operation is often a problem due to which the engine does not start well when hot. When carrying out the replacement procedure, use means for mounting electrical contacts, they can reduce the risk of failure.

Wiring spray can be used.

Poor quality gasoline

There is no narrow-minded method for assessing fuel quality. We have to use indirect signs, for example, a bad plant after refueling at an unverified gas station. At the same time, while your car does not start, there is a great chance to drain the battery, "kill the candles", clog the injector and even destroy the engine in case of incorrect detonation.

If the engine does not start well on a hot engine, the reason is probably an unsuccessful refueling. The solution to this problem is the use of additives in the gas tank, which improve the basic characteristics of gasoline.

To protect yourself from the consequences of refueling with low-quality fuel and to keep the injector in good condition, we recommend that you always keep a long-term injector cleaner for gasoline engines and a long-term diesel additive for diesel engines on hand.

Air filter problems

In winter, with a large temperature difference, a possible cause of problems such as icing of the air filter. Lack of air is also a reason that prevents the car from starting. In this case, it is recommended to replace the air filter immediately at the first sign of malfunction. The procedure is quite simple and does not require special skills.

IMPORTANT! One of the key factors provoking a poor cold start of a vehicle may be an incorrectly selected engine oil. If you have filled in oil with a viscosity of 10W-XX and higher, and severe frosts have hit, then the oil thickens and its pumpability in a cold system drops sharply, which leads to significant engine wear at start; as a result, the car will not start.

In winter, it is important to choose only high-quality oils from trusted manufacturers, as this guarantees the compliance of the oils with the declared parameters of "behavior" in the cold.

Reasons why a diesel engine does not want to start

The diesel engine is distinguished by the absence of spark plugs and the principle of compression ignition. Often the car will not start, because the diesel engine is very picky about the quality of the fuel, especially when driving in winter.

That is why you can protect yourself using special additives depressants, in common people - antigels. These additives prevent diesel fuel from freezing during cold periods. The range of such additives is wide, it is recommended to choose products from well-known manufacturers that have proven their effectiveness and safety. One of the leaders in consumer tests and reviews is the product of the well-known German brand, the LIQUI MOLY company. The product is distinguished by a high degree of fuel modification and absolute safety for diesel engine fuel equipment.

Low compression diesel engine

The second significant problem is the low compression in the diesel engine. Low compression can be caused by:

• wear of the cylinder-piston group;
• coking of the rings.

If only major repairs can help with the first problem, then the second problem is solved by high-quality prevention. During operation, carbon deposits, sludge and varnish contamination form inside the engine. The process is inevitable, over time a situation arises when carbon deposits do not allow the compression rings to work correctly. Compression falls, the pressure becomes insufficient to ignite the fuel mixture.

Prevention of such problems consists in the use of special flushing of the oil system to remove carbon formation. One of the best tools for this is a heavy duty oil system cleaner. The composition of the flushing was developed taking into account the application in the diesel engine, which allows to achieve the maximum effect from the application.

3 EASY STEPS TO AVOID MOST PROBLEMS WITH STARTING THE VEHICLE

One of the main problems in Russian conditions that cause a poor start of the vehicle is the quality of Russian fuel and the consequences of its use: deposits in the fuel system, clogging of injectors, injectors, etc.

For preventive avoidance of such vehicle problems, we recommend:

1. Check the battery before the winter season, replacing it every 3 years.
2. Use cleaning and lubricating fuel additives.

• Use fuel additives to remove moisture from the tank. One of the best additives is LIQUI MOLY's fuel additive.
• Clean the nozzles. We also recommend using LIQUI MOLY companies.
• When carrying out maintenance, it is imperative to inspect the condition of the electrical circuits of the car, clean them in a timely manner and use special protective equipment. For cleaning: safe contact cleaner. For protection: Electronic-Spray wiring spray.

1. For diesel engines, we recommend pouring antigel at every refueling in winter, especially in warm (!) Weather. This is due to the fact that some gas stations in warm winter weather can sell diesel fuel without a sufficient amount of expensive "winter" additives, and then cold comes and the engine will not start.

The most important rule of the correct operation of any car is correct and high-quality prophylaxis. As in medicine, it is easier to prevent a disease than to treat it.

In the article, we have considered only a small part of the reasons that can cause malfunctions of both the engine separately and the vehicle as a whole. But even this short article, we hope, will help to avoid many problems that arise during operation.

With the arrival of winter, black days begin for the car, as well as for its owner: ice, icy glass, frozen door and trunk locks, frozen brake pads ... But the biggest problem is cold. Moreover, if the air temperature drops below 20 degrees frost, the engine starts up equally badly on domestic cars and on foreign cars.

Why does the car start badly "on cold"

Poor cold start is associated with a number of reasons:

As you can see, all the reasons that make it difficult to cold start the engine are somehow connected with each other. And each of them contributes to the fact that the car does not start.

How to prepare your car for winter use

First of all, it is worth mentioning the fact that each cold start of the engine in terms of wear can be equated to a mileage of 150-200 km, and this value increases in proportion to a decrease in temperature, that is, the lower the temperature, the higher the degree of engine wear. Therefore, in order to keep wear to a minimum, care should be taken in advance.

To do this, even before the onset of cold weather, you should check the level of density of the electrolyte in the battery and, if necessary, recharge the battery. Although this, of course, will not save the battery from losing charge at subzero temperatures. Therefore, the best option is to do the same as the drivers of regions where the average daily winter temperature is -30 degrees: remove the battery at night and put it in a warm room. The several minutes lost in its removal in the morning will be more than compensated for by a trouble-free engine start.

It is better to choose oil for the winter period so that it does not change its viscosity in the cold, or at least it does not thicken much. Therefore, you should carefully read the description for the selected oil, paying special attention to the temperature range of its application.

Before winter, you should also install new candles and filters (air, fine fuel, oil). Moreover, it will be useful to carry one more set of candles with you, just in case.

The sequence of actions when trying to start the engine in frosty weather, in principle, is universal for all cars. Slight differences may be due to differences in fuel systems. Therefore, a cold start of a VAZ, GAZ or UAZ engine is performed in the same way as on foreign cars.

So, after a long stay in the cold, you first need to "wake up" the battery. To do this, the high beam turns on for 10-15 seconds, this will start a chemical reaction in the battery, and heat up the electrolyte.

The next step is to squeeze the clutch. This will decouple the engine and transmission, thereby relieving stress on the crankshaft. This is important, since even in neutral gear, the gears of the box will turn at start-up, and this will require additional energy from the battery.

You do not need to turn the starter for more than 5 seconds in one attempt, otherwise you can finally plant the battery or fill in the candles, and at low temperatures this is unacceptable. If the engine is in good working order, then from the 2nd, 3rd attempt it should start.

Until it starts to work steadily, the clutch pedal should not be released, otherwise the engine may stall. After letting the machine run at idle speed for 2-3 minutes, you can start a smooth movement (without jerks and accelerations), the engine warms up faster on the move.

There is a popular way to facilitate the morning start of a cold engine. To do this, in the evening, half a glass of gasoline is poured into the car's lubrication system, which will prevent the oil from thickening. However, this method is only effective if the engine is filled with mineral oil. It is not suitable for synthetics and semi-synthetics. And one more thing: after two glasses of gasoline in the lubrication system, the oil will have to be replaced, so this method, although effective, is rather suitable for emergency cases.

You can also use ether for a cold start, or, as it is also called, "quick start" (sold in car dealerships). For this, the air filter cover is removed and ether is injected through the throttle valves directly into the carburetor, after which the filter cover is tightly closed. Ether vapors, mixed with fuel vapors, will improve its flammability. Even a faint spark would be sufficient to ignite such a mixture.

It will also be useful, after parking the car, to pull out the throttle actuator regulator ("suction") to the end, thereby blocking the access of cold air to the still cold carburetor. This will prevent condensation from forming in it.

What if the battery is dead?

If the battery is still discharged, then the simplest thing in this situation is to "light a cigarette" from another car. This will require special copper wires with clamps ("crocodiles"). You need to be especially careful when lighting it, there are a lot of all kinds of electronics that can fail due to the resulting voltage drop.

You can connect the batteries without stopping the engine of the donor machine, the main thing is to strictly observe the polarity and sequence.

The connection begins according to the scheme from a weak battery to a charged one:

1. From the minus of the consumer to the minus of the donor.
2. From the plus of the consumer to the plus of the donor.

You need to be very careful not to confuse plus and minus, otherwise the battery may explode!

After connecting, you need to let the "donor" work for another 5-10 minutes at idle, so it will recharge the planted battery. Then his engine should be turned off, and only after that try to start the consumer. If this is not done, then the voltage surge that occurs when starting the powered motor can severely damage the electronics of the "donor".

When none of the above helps, all that remains is to pull the car in tow or push.

How to start a car from a tug

Starting a car from a tug is not difficult, but it must be done correctly. To do this, the ignition is switched on, the car is put in "neutral", and you can start moving. After gaining speed (40 km / h), the clutch is squeezed out and the third gear is immediately engaged (so the load on the engine will be minimal) and the clutch is smoothly released. If the engine starts, do not stop immediately, the car may stall. It is necessary to wait until the engine starts to work steadily (rpm will stop floating).

Engine revolutions when starting "cold" usually fluctuate between 900-1200 rpm, and after warming up they drop to 800.

Another problem with winter car operation is when, after a cold start, a whistle is heard from under the hood, which may disappear after warming up. Nevertheless, this cannot be ignored.

What can whistle under the hood after a cold start

If a whistle is heard from under the hood of the car when starting the engine to a cold one, then there may be several reasons for this:

It must be remembered that any extraneous sound under the hood is a kind of warning about some kind of malfunction, and if you cannot independently determine the cause of the sound, then you need to contact the service station specialists, and you should not delay with this. After all, "breaking" somewhere in the middle of the road in a bitter frost is a dubious pleasure.

Difficulties with starting the engine "cold" arise in different situations. Firstly, the long stay of the car in the cold. It can be one night or several weekends. Secondly, the cooling of the internal combustion engine after it warms up to operating temperatures, stops and attempts to restart after a while.

Difficulty starting a gasoline and diesel engine has similar reasons, but manifests itself in different ways. This applies to engines with a carburetor and injection fuel supply system, which have structural differences.

In this article, we will talk about common problems that lead to additional difficulties when trying to start the engine "on cold", we will give recommendations for car owners with power plants running on gasoline and heavy fuel.

Preparatory activities

To simplify our task in finding the cause of the malfunction, we check the following:

1. The presence of exhaust gases.

A light smoke should come out of the exhaust system during the rotation of the starter. It indicates that fuel is entering the cylinders.

2. Battery charge level.

A completely discharged battery is one of the most common reasons why a car engine won't start. Therefore, we check the battery charge level.

3. Serviceability of the starter (must "turn" the engine without failures).

If the starter does not spin the crankshaft, then a dead battery is to blame. If not, then the malfunction lies elsewhere. For example, the contact between ground and the starter housing has oxidized.

The main causes of cold start problems

1. Low quality fuel

The likelihood of refueling a car with low quality fuel at certified gas stations in large cities is very small. It is much easier to encounter counterfeit products at little-known gas stations on highways or when buying fuel from hand. Such fuel does not pass quality control and contains a large amount of impurities that contaminate filters and fuel lines. As a result, the pressure in the system decreases and the car will not start.

The use of low octane gasoline is determined by the following criteria:

• too noisy operation of the internal combustion engine;
• decrease in the dynamic characteristics of the car;
• detonation.

In diesel engines, a problem may arise due to the selected fuel "out of season". The owner using diesel fuel for the summer in the winter period of vehicle operation will face difficulties. The main reason is the discrepancy between the physicochemical properties of the fuel and the operating conditions.

Summer diesel fuel at negative temperatures turns into a viscous and thick mass that clogs both the fuel line and the filter. Its chemical composition is not adapted to work in such conditions. In this situation, preheating the fuel system and installing a new filter instead of the dirty old one will help.

2. Poor spark plug condition

Remove the spark plugs after a failed attempt to start the engine. The presence of strong smudges, as a rule, indicates a malfunction with the ignition system and a violation of the tightness of the injectors.

First you need to inspect the external condition of the candles. Check their integrity. Look at the high voltage wires. There should be no defects.

A dry candle indicates that no fuel is entering the cylinder.

3. Problems with the fuel pump

Malfunctions in the operation of the pump make it impossible to build up the required pressure level. The main reason for this unpleasant phenomenon is a clogged filter. If the filter element is dirty, the required pressure is not generated in the rail. Accordingly, the car will not start. The combustion engine is supplied with a lean fuel mixture, which, moreover, does not ignite due to the too low temperature in the cylinders.

To find a malfunction, we check the pressure in the rail and directly in the pump. Engines with an injector power supply may also have carbonized injectors.

To check the fuel pump, turn on the ignition. If everything is in order, then you will hear a characteristic hum from the side of the fuel tank. It lasts a couple of seconds. After stopping the fuel supply, the required pressure will build up in the fuel rail. The pumping equipment should automatically shut down.

4. The presence of air leaks

The air supply system must be sealed. To check if it is coming in, look at the status of the trunk. It should be free of cracks, fractures or kinks that lead to leaks or obstruct the passage of air. Traces of gasoline smudges are evidence of leaks in the fuel lines.

5. Error when choosing engine oil

It is admitted by inexperienced car owners. An improperly selected engine oil in terms of viscosity leads to problems when starting the internal combustion engine. Too thick liquid solidifies at low temperatures. As a result, difficulties arise with its passage through the oil channels.

6. Malfunction of the idle valve

The idle valve is an electromagnetic element with a stem. It is controlled by the power unit ECU. When it's frosty outside, the internal combustion engine temperature sensor transmits the corresponding information to the ECU, and the ECU signals this to the idle valve. Its stem extends to open the throttle valve. As a result, the engine speed increases in a cold state. When the internal combustion engine is warmed up, the reverse process takes place. As a result, the stem returns to its original position. The engine speed is reduced.

If the idle valve fails, then the stem either remains stationary or does not extend fully. Problems can be caused by a broken coil inside the sensor housing, or by excessive dirt on the sensor.

7. Violation of valve clearances

A common reason why the engine does not start well in both carburetor and injection engines, especially when cold.

8. Damage to explosive wires, contamination of the throttle valve.

The presence of a large amount of dirt in the throttle valve interferes with the air regulation process. This is a serious problem for starting the motor. The fact is that the internal combustion engine receives untreated air containing dust and oil deposits, which do not allow the formation of a fuel mixture of the required consistency.

These malfunctions are typical for diesel and gasoline power units. However, there are several problems that owners of vehicles with a certain engine design have to face.

Problems with starting the carburetor

For carbureted internal combustion engines, the most common failure is in the ignition system. This applies to BB-wires, switch, breaker-distributor, coil. The engine may not start due to the battery, damaged pump diaphragm or starting device.

There are many reasons. However, it is better to start your search with candles. Unscrew the devices for ignition of the air-fuel mixture (FA). If they are wet, then look for a fault in the car's electrician.

With a cold start, a carburetor power unit can be cheated. For example, pump a little more gasoline fuel or increase the suction. After these procedures, the power unit starts up better. However, the car owner needs to be sure that the carburetor is fully functional and has the correct settings. Switch problems or faulty spark plugs can negate the owner's efforts.

Video: Why is it difficult to start a cold carburetor?

In the DAAZ and Solex carburetors, the following phenomenon can be observed: the engine starts up, and after a while it stalls. If the candles are flooded, then the starting device is to blame for stopping the internal combustion engine, or rather, its diaphragm.

Consider the common cases when problems arise with starting a carburetor-type engine.

1. The starter spins the crankshaft, but does not "catch" (problems with the flow of fuel, there is no ignition).
2. "Grabs", but does not start the internal combustion engine (problems with the ignition).
3. Does not spin the crankshaft (the battery is discharged).

Owners of cars with carburetor internal combustion engines who encounter problems during cold start, it is advisable to check for possible places of malfunction in the following order:

• spark plug;
• wires (high voltage);
• starting device;
• idle jet;
• breaker contacts;
• ignition timing;
• fuel pump;
• tube of the vacuum amplifier.

There is one more useful advice that will be useful to the owners of domestic cars. Try to slowly (without jerking) sink the gas pedal and turn the starter. Then release the throttle to find the moment when the clutch “grabs”. To start the engine, keep the gas pedal in the found position until warming up.

Injection engine starts poorly

In cars with an injection engine, a variety of sensors are a weak point. Their incorrect operation leads to a difficult start of the motor, since the ECU receives incorrect information. This remark is valid for the following types of sensors:

• throttle flaps;
• fuel consumption;
• intake manifold pressure sensor (DMRV).

In injection power plants, the coolant temperature sensor also influences starting. The thermistor sends data to the control unit containing information about the condition of the coolant. The incoming signals affect changes in the composition of the air-fuel mixture.

In injection-type engines, a common reason that the engine does not start on a cold one is that the fuel pressure regulator is to blame. With certain difficulties when starting the internal combustion engine "to cold", but the disappearance of problems after warming up, check the condition of the spark plug wires, the spark plugs themselves and the coils.

Leaky injectors cause many problems for car owners. Due to leaking fuel sprays, the power unit hardly starts up not only "cold", but also after a certain time of operation (even in extreme heat outside). To test this theory, you can bleed the pressure from the fuel supply system in front of the overnight stop, and in the morning you can look at the result.

Useful advice for owners of cars with an injection engine. If there are no problems with the starter, devices for igniting fuel assemblies and wires, then you should look for a malfunction in the coolant sensor. It is worth checking the pressure indicator in the fuel supply system.

Video: a problem with starting a cold engine VAZ 2112

Will not start on cold diesel

With the launch of diesel engines, other problems come to the fore. One of the main ones is weak compression. It is determined by the following criteria: the car does not start on its own after a night in the cold (only from the "pusher"), a small dark gray smoke comes out of the exhaust system. The presence of the latter at the time of cranking with the starter indicates the absence of problems with the supply of fuel, but certain difficulties arising when the mixture ignites.

In engine cylinders with low compression, the gaps between the elements increase. Therefore, it is problematic to start the engine "cold". There is no pressure in the combustion chamber required to ignite the air-fuel mixture at the start of the internal combustion engine.

Why is this happening? First of all, it is worth checking for severe wear or serious damage on the following parts:

• pistons and piston rings;
• cylinder walls;
• valve of the gas distribution mechanism.

Low compression is a common occurrence in high-mileage passenger cars and trucks. Their owners are faced with the fact that the power unit starts up with serious problems both in severe frost and in more favorable conditions.

Starting problems are also associated with the low quality of the diesel engine, which contains a large amount of impurities, and the breakdown of the spark plugs. If everything is more or less clear with the fuel, then the glow plug does not function for various reasons:

• oxidation of the connection connector;
• relay failure.

Let us dwell on the second problem in more detail. A sensor is responsible for the operating mode of the relay, which controls the temperature of the coolant. If it is working properly, then the driver hears clicks when turning the key in the ignition lock. If there is no characteristic sound, then the problem is clearly related to the spark plug relay.

If there is good compression, the engine will start in frost even with poorly functioning candles. However, in the first minutes of engine operation, rpm jumps will be observed.

Do not write off fuel injectors. Their heavy wear or contamination interferes with the normal operation of the internal combustion engine. In some situations, the fuel filter is to blame for interruptions with cold starting of the engine. The injectors can throw off a large amount of fuel into the "return line". This is established only during the test.

Seal

Along with high efficiency and relative reliability, injection vehicles have one unpleasant disadvantage - the complexity of repair. It happens that the injector stops starting in an instant, and it becomes difficult to do something with it. It is good if there is an opportunity to call a tow truck or show the car to a professional, but what should those motorists who are left with a one-on-one problem with? Let's figure it out, having considered in detail all the reasons why the injector does not start well or refuses to do it at all, as well as how to "treat" such a malfunction.

Possible malfunctions

No matter how trite it may sound, if the injector does not start, then something is out of order. The success and speed of the repair depends on how quickly and efficiently it is possible to identify the problematic link in the vehicle design. For a better understanding of the whole essence of repair measures, it will not be superfluous to pay attention to potential breakdowns. The basic list of the latter is as follows:

• Faults directly in the injector. In the event of a breakdown of this kind, as a rule, the car will not start both cold and hot. In addition to everything on the dashboard or on-board computer, the injector indicator is constantly on, signaling its malfunction. Much less often, when the indicator is on, the motor works, but in this case the car does not start well and is extremely unstable. It is worth noting that in the injector nozzles are most often clogged or the computer burns out, therefore it is advisable to check these units first;
• Breakdown of the ignition system. Here the list of possible malfunctions is quite large. Often candles suffer, which are simply flooded. In case of such a breakdown, the car starts up and immediately stalls, in the long run it stops even "grabbing". Other components of the ignition system (coil, module, distributor, crankshaft sensor, etc.) suffer noticeably less often;
• Incorrect operation of the fuel system. In this aspect, injection engines most often suffer on three fronts:
  1. The fuel filters are clogged (the car “picks up” but does not start, but if the engine is running, it is extremely unstable);
  2. The fuel pump is faulty (its characteristic sound is absent when the ignition key is turned, the injector itself simply does not start both cold and hot, the starter turns).
• Insufficient pressure in the fuel system (both on cold and hot, the engine is reluctant to start, but if it works, it functions unstably);
• Engine problems. Perhaps the widest range of possible malfunctions. Oftentimes, the cause is poor compression or improperly adjusted valves. In any case, with a "motor" problem of starting, high-quality diagnostics of the engine is required, otherwise it will be very difficult to determine the cause of the malfunction.

In addition to the breakdowns described above, which can break the operation of the injector, the problem may lie in more banal things. An example of this is a weak battery charge or lack of fuel in the tank. Taking into account such incidents, it is extremely important to exclude the possibility of their manifestation before repairing a car, so as not to waste extra time and nerves.

Procedure for returning the car to "life"

Let's say that you are specifically in circumstances where the injection engine does not start well or refuses to do it at all. There is no need to hesitate in such a situation - it is advisable to immediately start resuscitation procedures. If you deal with the exact reason why the car does not start well, there is no time, then you should quickly carry out the following algorithm of actions:

1. First of all, we check the availability of gasoline and battery power. Isn't there something? Fill in, "light up". Trying to start. If there is no result, proceed to the next step;
2. Next, we quickly analyze under what circumstances the car malfunctions. If it starts up for a long time or badly on hot, first of all we check the spark plugs for overheating (light carbon deposits) and the functioning of the fuel system. Otherwise, when the machine malfunctions both cold and hot, a more comprehensive approach is required. As a rule, the following procedures are enough: checking the spark plugs, wiring the ignition system, evaluating the operation of the injector and the fuel system;
3. Note that most motorists manage to solve the problem, so to speak, with little blood, that is, through the implementation of the actions described above. If it is you who are not among the lucky ones and your car still takes a long time, starts poorly or refuses to work at all, you will have to act globally. It is better to drive the car to a service station or a convenient garage and check the compression, timing adjustment, clean the injector, assess the condition of the fuel system, ignition devices. If there are any faults, they must, of course, be eliminated.

In general, there are no particular difficulties in repairing a non-starting injector. The main thing in the process of such work is to act competently, according to the procedure described above and possible vehicle malfunctions.

Prevention of injector breakdowns

Why the injection engine does not start and how to eliminate possible problems are now known to all readers of our resource. However, it is better not to allow such breakdowns, so let's pay attention to the usual procedures, which, if carried out systematically, will help to minimize the risks of all malfunctions. The simplest but most effective prevention consists of the following measures:

• Firstly, refuel exclusively at proven gas stations and only with high-quality fuel. Remember that most fuel system and engine malfunctions are provoked by dirty gasoline;
• Secondly, change all consumables on time and only with quality products. The most important is the periodic replacement of all kinds of filters and engine oil;
• Third, periodically check the stability of the main parts of the machine. The list of the latter, of course, includes an injector, elements of the fuel system, ignition and engine;
• Fourthly, never neglect the scheduled diagnostics of the car at the service station. Surprisingly, even a delay of a couple of hundred kilometers can cause serious breakdowns, which previously could have been eliminated by very simple actions;
• And fifth, always operate your vehicle properly. That is, you do not need to overheat, overload and negatively affect your car in any other way.

Most modern cars are equipped with a fuel injection system. The system is installed only on gasoline engines. Despite the complexity of the design and high requirements for fuel quality, the injection engine has a number of advantages over the carburetor mechanism:

• automatic adjustment of the injection system depending on the load;
• quick start of the engine, an increase in its dynamic performance;
• low emission of harmful substances;
• saving fuel consumption due to metered injection;
• does not need long-term heating during low temperature conditions;
• the ability to program the electronic control system, depending on the manner and driving style;

How the engine works

In principle, injection engines are similar to diesel engines: fuel is supplied through special nozzles. After the starter starts cranking the crankshaft, the control sensors send a signal to the electronic control unit, which indicate in which stroke the cylinders are located.

After reading the data, the control unit sends a signal to the injector of the cylinder, which is in the intake stroke. The injector opens for a strictly defined time, which corresponds to the readings of the mass air flow sensor.

Table of values ​​of mass air flow sensor.

After the end of the intake stroke, compression occurs. The central module receives data from the DPKF and DF sensors that the piston is at top dead center. After processing the data, the signal is sent to the ignition unit, which transfers the voltage to the desired cylinder. The task of supplying voltage correctly is provided by two transistors located in the control unit housing.

Further, when the ignition of the working mixture occurred, the cylinder began to operate in the combustion chamber, the ECU receives the readings from the knock sensor and adjusts the ignition angle for the next cylinder.

For more efficient use of fuel energy, an oxygen sensor is installed in the exhaust system. Using the indicators received from the sensor, the control unit adjusts the composition of the mixture, sets the opening time of the nozzle. If there is a lack of oxygen when the throttle is open, the ECU opens the idle speed controller.

Reasons for improper operation of the injection engine

There may be several reasons why the injection engine does not start well when cold. The main one is sensor malfunction.... If one of the modules breaks down, the electronic control unit receives incorrect data, from which the engine starts poorly and runs intermittently.

Common causes of poor starting of an injection engine.

Air leaks

It occurs when there is a leak in the parts of the air supply system. The mass flow sensor cannot capture some of the air entering the engine, which is why a lean mixture is supplied to the combustion chamber. This leads to erratic idling and a cold start problem for the injection engine.

During warm-up or suction operation, this problem is almost invisible, but when the engine heats up to operating temperature, idling interruptions become more noticeable.

Air leaks can occur for the following reasons:

• violations of the tight connection in the vacuum amplifier;
• mechanical damage to the fasteners and the air supply hose to the intake manifold, pipelines of the pressure regulator and the crankcase ventilation system;
• damage to the gaskets between the cylinder block and the intake manifold.

The cause of air leakage can be determined by visual inspection. If the malfunction significantly affects idle operation and starting a cold injection engine, before repairing, you can increase the speed by disconnecting the plug from the mass flow sensor. This action will lead to a significant increase in fuel consumption, so it is not recommended to delay the repair.

In case of insignificant suction, it is enough to adjust the fuel supply using the L-probe device.

The main indicators of the fuel and air mixture

Fuel mass, kg.	Air mass, kg	Excess air factor	Mix names	Combustion rate	Engine power	Application mode
>1:6		<0,41	The mixture is non-flammable
1:6	1:11	0,41 - 0,75	Rich	Reduced	Reduced	Cold start
1:11	1:13,7	0,75 - 0,92	Enriched	Maximum	Maximum
1:13,7	1:15,4	0,92 - 1,05	Normal	Average	Average	Used with an exhaust gas neutralizer
1:14,7		1	Stoichiometric	Average	Average	Used with a neutralizer
1:15,4	1:17,7	1,05 - 1,2	Depleted	Reduced
1:17,7	1:20	1,2 - 1,36	poor	Sharply reduced	Loss of power	Does not apply
<1:20		>1,36	The mixture is non-flammable

Mass flow sensor malfunction

Incorrect operation or breakdown of the sensor leads to an instantaneous stop of the motor after starting. When this happens, you need to disconnect the sensor and re-start the car. If the engine runs smoothly, then the flow sensor needs to be replaced.

Temperature sensor defective

When the central control unit receives no signals from the coolant temperature module, it assumes a zero value. The built-in program prepares the working mixture according to this temperature, which leads to the following consequences:

• injector the engine does not start well when cold;
• detonation at low speeds.

The module is not repairable, so the defective part is replaced with a new one.

Defective ignition

The problem can be corrected by setting the moment the spark is supplied, adjusting the position of the timing belt and replacing damaged parts.

Table of resistance indicators of the temperature sensor from the temperature of the cooling medium.

A breakdown in the fuel regulator leads to leakage of fuel into the combustion chamber through the intake manifold pipes. As a result, a rich mixture enters the engine, which leads to severe plugging of the spark plugs. This malfunction significantly affects the cold start of the injection-type engine.

Camshaft phase sensor

A breakdown leads to the transition of the fuel supply mechanism in emergency mode, in which the injector delivers fuel twice as much as necessary.

Reasons for replacing the module:

• difficult start;
• interruptions in the vehicle self-diagnosis system;
• significant increase in fuel consumption;
• smoke in the exhaust mechanism.
• difficult cold start of the injection engine

You can fix the problem by self-adjusting the position of the sensor or contact the service center.