The carburetor is sucking in air for signs. How to find air leaks in the engine and eliminate it. Manifold Leakage Symptoms: Check and Identify

All car engines, regardless of their type (with an injector or a carburetor), run on a mixture of fuel and air. The ratio of these components in the mixture is precisely calculated and regulated either electronically or mechanically.

But, sometimes it happens that an additional air leak occurs, the mixture is "diluted" and the motorist can observe a serious loss of power in his car (which is especially noticeable at low revs). Why this is happening and how to fix this situation - we will talk in today's article.

Air leaks and its signs

Such a phenomenon as suction is associated with the penetration of air into the fuel path of the machine. It leads to a lean mixture and, as a result, greatly affects the operation of the engine, reducing its power and causing interruptions in operation.

If air leaks in the intake manifold, the symptoms of the VAZ 2114 may be as follows:

• unstable idle speed;
• tripping the engine;
• "Sagging" during acceleration;
• increased gas mileage;
• difficult starting even at high air temperatures;
• a sharp drop in power (especially at speeds less than 3.000 min-1).

If the engine stalls very often, then this may also indicate that there is an air leak in the VAZ 2114. Additionally, you can make sure that this problem exists using a car scanner. The presence of suction can be indicated by errors P0171 (very lean mixture) and P300 (misfires are observed).

Stable operation of the engine at high speeds does not at all mean the absence of suction, since it is most clearly manifested precisely at low speeds. It is worth remembering about this, so as not to be misled and not start looking for other causes of problems.

As soon as you notice that there are signs of air leakage, you should immediately start looking for a possible place for its penetration into the system.

Potential suction points

There are quite a few places through which air can enter the fuel system, and during the check you will have to investigate all of them (we will talk about exactly how to find them below).

For now, let's say that we have to check:

1. 1. Intake manifold gasket (its destruction or burnout in the overwhelming majority of cases is the cause of the suction).

1. Hoses and fittings to fit the manifold.
2. Injector seals.
3. Throttle gaskets.
4. Plugs located on the manifold.
5. Bushings.
6. Vacuum-type brake boosters.

If symptoms of air leakage in the VAZ 2114 injector appear, all these elements will have to be checked.

You should also check and, if necessary, replace the idle speed sensor. Very often they are of poor workmanship and are leaky, leading to the ingress of air into the manifold.

How to find the suction site

There are 3 main methods by which you can find a leaky area:

• by monitoring the air rarefaction in the line;
• using a smoke generator;
• using a volatile flammable liquid.

We will omit the first method, since it requires special equipment, which is not available at all service stations. But the second method deserves a lot of attention, since it is quite simple to implement and at the same time very accurate. It will require a compressor, a blow gun and cigarettes (the latter will serve as a source of smoke).

Before checking the air leakage of the VAZ 2114, you will need to assemble the entire installation, namely, connect the pistol to the compressor receiver, and insert a cigarette into the pistol nose. After that, a pressure of about 0.8 atmospheres is injected and the smoke is sent to the manifold with a pistol.

The smoke itself, created by such an installation, is quite thick, and quickly fills the entire system. All that remains for the motorist is to carefully monitor the place where the smoke comes out, and after its detection, to carry out repair work.

In some cases, the suction can be found without additional means - the damaged area can be easily detected by the characteristic whistle or hiss that the intake air produces when the engine is running. True, this only happens in the presence of serious cracks and ruptures.

If the proposed method using a smoke generator is not suitable (for example, there is no compressor available), then the check can be performed using volatile flammable liquids packed in pressurized cartridges. Ethyl ether can be used as them (however, in its pure form it is practically impossible to get it now), a means for winter starting diesel engines (the main component of which is the same ether), as well as special cleaning agents based on hydrocarbons.

In order to find the place of the suction, you need to start the car engine and, at idle, start spraying all possible nodes, joints, plugs and hoses that belong to the manifold and can be the cause of air penetration.

This should be done with pauses - after spraying one place, you should wait a few seconds. If you notice that the engine speed has increased sharply after the procedure, then the detected area should be densely sprayed again. If after that the revolutions quickly go up again, then the suction site has been successfully found.

Useful video

You can find additional interesting information on this issue in the video below:

Air leaks - how to find? Diagnostics. Kazan.

Air leaks in the intake tract- a very unpleasant malfunction. It can manifest itself in completely different ways - it depends on the degree of suction.

The essence of the malfunction lies in the fact that unaccounted for by the mass flow sensor, air enters the engine. This leads to a leaner air-fuel mixture. It manifests itself in the unstable operation of the engine, especially at idle, sagging up to a complete stop of the engine when driving in neutral. Errors on the oxygen sensor associated with the depletion of the mixture, an error on the adsorber, and misfire in the cylinders may appear.

Sometimes it is very problematic to determine the place of air leakage, especially if air leakage occurs in the area of ​​the gasket between the cylinder head and the intake manifold.

Where to start your search if you decide to do it yourself? Start the engine, leave it idling. Listen for a characteristic hiss of air. The sound will make it easier to search. If it is not possible to localize the source of the hiss, start alternately pinching the hoses going to the intake manifold with the NIPPERS (!). Usually this is a hose of the vacuum brake booster, a hose to the adsorber valve, a hose to the fuel pressure regulator. If, when you pinch any hose, the engine performance improves significantly, or when you release the pinched hose, a noticeable jump in speed occurs, the problem is there. These are either faulty, leaking mechanisms (adsorber valve, vacuum booster ...), or hoses damaged to holes.

If nothing worked out by ear and with round-nose pliers, use a spray of some flammable liquid. This can be a carburetor cleaner, vadashka, and similar chemical cans. It is possible with paint - but it gets very dirty…. We use a 1-liter plastic bottle with a thin tube from a vdeshka inserted into the lid. A syringe needle will work too. The bottle contains ordinary gasoline. The goal is to accurately hit potential air leaks with a thin stream of gasoline. This is the joint between the cylinder head and the intake manifold, the entry point of the nozzles into the manifold, the joint between the throttle pipe and the receiver, the inlet rubber corrugation, the seams of the plastic receiver and other suspicious places. When gasoline gets into the place of suction, it is instantly absorbed and enters the combustion chambers. The engine speed at this moment sharply changes up or down.

The final method for detecting air leaks is a smoke generator test. Through any opening in the intake tract, under light pressure, the smoke is driven, obtained by heating automobile engine oil with secret additives for greater smoke. In the bright light of a halogen lamp, plumes of smoke can be seen escaping through the inlet leaks. The procedure is quite effective, but we have not yet fully mastered it - there is a smoke generator - there are various adapters left for connecting to a car to purchase. Coming soon!

And, finally, the most problematic areas of VAZ cars are air leaks.

The rubber plugs of the receiver do not stand up to any criticism. Two plugs are exchanged for one piece of vacuum hose about 10 cm long. One end of the hose for one pipe - the other end of the hose for the second pipe - and there is no suction! The hose must be taken vacuum white!

Often on the exhaust manifold there are hoses from the throttle pipe to the adsorber valve and the vacuum booster hose, from which they suffer. After replacement, it is necessary to carefully fasten them to their regular places with special brackets or clamps.

Vacuum boosters often begin to suck in air, especially if the brake master cylinder begins to leak. When replacing the vacuum cleaner, do not forget to deal with the GTZ leak!

There are exotic things like a fallen off back cover of the idle speed regulator, damage to the membrane of the fuel pressure regulator, jambs from unqualified or self-assembly of the intake, replacement of parts and sensors.

Reading 6 min.

For a car to drive well, it must be well looked after. DPDZ is a device in a car that changes the angular position of the throttle valve. But do the same if your car has air leaks through the throttle column.

The throttle position sensor is used to detect the speed and degree of opening of the throttle valve. The throttle position sensor, or as it is abbreviated as TPS, is a device that was originally designed to convert the angular position of the throttle valve into a DC voltage. This sensor is considered one of the sensors in all electronic engine management systems of a fuel injection vehicle. After receiving a signal from the throttle position sensor, the controller monitors the angle by which the throttle valve is deflected. Based on the information received from the throttle sensor, the electronic control unit selects the fuel transfer mode.

In this article, we will try to answer the following frequently asked questions:

• Air leaks through the so-called throttle valve;
• Throttle valve malfunction signs;
• How to remove oil in the throttle valve?;
• What to do if after cleaning the throttle body the revs have risen?
• Cleaning and adjusting the throttle valve.

Throttle valve malfunctions and methods of their elimination

Before discussing the diagnosis and symptoms of a throttle position sensor, let's talk about the significance of the sensor. The throttle position sensor plays a huge role in the control of the car's engine, because thanks to its readings, the control unit calculates the fuel proportions, as well as corrects the ignition timing. In the event of a breakdown of this sensor, the driver is immediately notified of the error via the control unit. An error notification appears on the dashboard, namely, you will see a light bulb - “Chek”. Please note that the error that occurs only indicates a malfunction in the throttle position sensor circuit, but cannot localize it. That is, if the sensor settings are violated, the unit will not be able to recognize the error.

To eliminate a breakdown, each driver needs to know the elementary signs of a malfunction. Many drivers, when faced with such a problem, decide to clean or replace the throttle valve, but after that the revs may rise. In order to return the previous rpm, you need to adjust the throttle, and we will tell you exactly how to do this a little later.

The electrical engine management system detects failures related to wire breaks or short circuits. There may be some signs of malfunction in the ignition and power supply system. Also, due to a breakdown, air leaks through the so-called throttle valve may occur or the speed may rise. The turns have certain external signs, but the error codes are not marked in the memory of the electrical unit. Consider the main signs of breakdowns:

• Slight difficulty in starting the engine;
• Dips or jerks are felt during the operation of the engine;
• Small enough power;
• Frequent occurrence of detonation;
• Failing, holding and twitching;
• Engine operation with slight interruptions;
• Increased fuel consumption;
• A specific gasoline smell arises in the exhaust system during gasoline processing;
• Instability during the operation of the engine, and during operation on a cold run it stops;
• Sometimes the fuel mixture ignites spontaneously;
• Some pops are heard in the intake manifold or muffler.

If you find any of the above malfunctions, but the self-diagnosis system does not determine the breakdown code from the throttle position sensor, you do not need to jump to conclusions and change it. In this case, the malfunctions you find may be caused by completely different reasons.

Now let's talk about how to diagnose air leaks through the throttle. Before correcting the reasons for the air leak, familiarize yourself with the consequences. Naturally, after avoiding problems with air leaks, unpleasant consequences may arise, namely, the speed will increase. In order to determine if air is leaking at all and its reasons, check the following places:

• Throttle valve and its axis;
• Cold start nozzle;
• Corrugation behind the throttle position sensor;
• The inlet of the crankcase cleaner located on the corrugation;
• Throttle body and corrugation connection;
• Nozzle rings;
• Conclusions through which gasoline vapors escape;
• The tube of the vacuum brake booster.

How to check the places where air leaks can occur?

• Use diesel fuel to spill the nozzles;
• Disconnect the mass air flow sensor from the air filter housing and cover it with your hand. After that, the corrugation should shrink a little and, at best, due to the fact that the air suction has stopped, the engine will stall;
• Disconnect everything except the throttle valve and close it with your hand. After that, due to the fact that the air suction has stopped, the engine should also stall;
• Spray places where air is leaking with a carbcliner.

Cleaning and adjusting the throttle valve

We figured out how to diagnose air leakage and now we will discuss the consequences that may arise. Once there, and more often than not, air is leaking, I cleaned the throttle valve, but after that the revs went up. And this is a fairly popular problem! Quite often, drivers have the following question: I cleaned the throttle valve, and after that the revs increased greatly. What to do?.

So, after you have a question like “I cleaned it up, what should I do next? My turnovers have risen! " don't worry. The reason your turnover went up is most likely due to improper regulation. Checking and regulation must be started by turning on the ignition. If the light does not light up, then go directly to the throttle position sensor itself. Here, using a multimeter, it is necessary to check the minus. Pierce the wires one by one and look for mass, but do not turn on the ignition. In the same way, you can make sure that the power supply chain is in good working order; for this, pierce the wiring one by one. Then we move on to performing the following basic tasks:

• Make sure the idle contacts open;
• Check the condition of the tracks that carry current and the film resistor.

On the throttle position sensor connector, find the idle contact and place the multimeter probe on it, and then move it. If the sensor is correctly adjusted while driving, the voltage will immediately begin to change from zero to the supply voltage. The coating of the variable film resistor has a strong influence on the smooth functioning of the throttle position sensor, and this is very important for the correct perception of the data by the engine control unit. Place the dipstick on the last wiring and slowly move the throttle. After that, the voltage should rise slowly without any jumps or dips.

Regulation algorithm:

• Remove the corrugated tube and check the condition of the throttle valve;
• Using a cotton wool soaked in gasoline, wipe the intake manifold and flap;
• Unscrew the stop screw of the damper to the end and release it sharply;
• Adjust the pressing of the screw and then click the flap. After stopping biting of the damper, check the screw with a nut;
• Place a multimeter probe on the idle contact and between the stop screw and the shutter;
• Turn the sensor body until the voltage starts to change and the damper opens;
• Secure the screws.

Any internal combustion engine must operate on a mixture of air and fuel, which are tightly controlled by electronics, if it is an injection engine, or mechanics, if it is a carburetor engine. Any imbalance in the proportion of air and fuel leads to incorrect engine operation, a drop in power, and an increase in fuel consumption. Intake manifold air leaks can severely affect engine stability. How to check and determine the malfunction, identify the main symptoms of suction, let's figure it out right now.

Manifold Leakage Symptoms: Check and Identify

Clear signs of a cracked hose

Any unauthorized penetration of excess air into the power system leads to a depletion of the working mixture. The optimal balance of fuel and air is violated, as a result of which the engine pounds, idle speed can disappear altogether, while at speeds above 2-3 thousand the engine can work quite tolerably.

Error P0300

In addition, the electronic engine control unit can show a number of errors - P0171, lean mixture, an error may appear P300, talking about misfire in the combustion chamber. Several other errors may occur depending on the engine model.

Nevertheless, the main symptoms of air leakage in the intake manifold are:

• unstable idle speed, the engine shakes, it is impossible to adjust idle;
• the engine may stall in transient modes of operation;
• dips during acceleration;
• high fuel consumption;
• difficult start at any air temperature;
• drop in power, especially at speeds below 2-3 thousand;
• the engine is troit, one or more cylinders do not work in certain modes.

Where can the air be sucked in?

One of these symptoms is enough to talk about air leakage in the intake tract. It can be quite difficult to pinpoint the exact location of the air intake, since the place of attachment and sealing of the intake manifold to the cylinder head is far from the only way to suck in excess oxygen.

Depending on the engine model, there may be several places of suction:

1. Damage or burnout of the gasket the intake manifold is one of the most common places for leaks.

   New intake manifold gaskets

2. Seals for injectors in injection motors.
3. Backlash and leaks in the axles of the throttle valves of carburetor engines.
4. Vacuum brake booster.
5. Connections and hoses that are fixed to the manifold.

   A leaky hose on the manifold caused an air leak

6. Throttle gaskets in injection motors.
7. Valves of the adsorber, plugs on the manifold, leaks in the sensors.
8. Idle controllers of questionable quality may be leaking.

   Leaky idle speed control

9. Bushings.

As you can see, troubles can be expected not only from the gasket of the collector or the collector itself, at the same time there are a number of measures that will help to find the place of breakdown and quickly eliminate the malfunction.

Determine the place of air leak

The most effective way to determine the location of an air leak is visual.

True, for this you have to either find or assemble the simplest smoke generator. Smoke launched into the intake system will instantly show the place of suction with high accuracy. It is clear that not even every service station has a smoke generator, so the simplest device can be assembled by hand.

Do-it-yourself smoke generator

For this, a blowing air gun, a compressor with a receiver and a pack of cigarettes for smoke will come in handy. The pistol is simply connected to an air receiver or compressor, a cigarette is inserted into the nozzle of the pistol, a pressure of about 0.5-0.8 atm is injected, and the smoke under pressure enters the intake manifold.

Homemade smoke generator

The flaw will become noticeable as soon as the smoke finds a place to exit.

Another way to find the place of "suction"

The second method for determining the location of the suction is more time consuming and time consuming. For this it will come in handy flammable liquid(ether, gasoline with a high octane number, liquid for quick start of the engine in a can). To check and determine the place of suction, it is enough to start the engine and spray liquid on the manifold interfaces.

Sometimes the suction is clearly audible by the characteristic whistle or hiss, but this does not happen in all cases. Therefore, it is necessary to methodically spray with liquid the place where the intake manifold meets the block head and all the suspicious connections that we have listed above. As soon as the liquid enters the place of breakdown, it will be sucked into the intake tract and the engine speed will sharply increase for a while.

other methods

There are several more methods for detecting suction. They consist in the accurate measurement of the vacuum in the section from the throttle valve to the combustion chambers, however, the equipment used to implement this method is not always available, and the accuracy of localizing the place of depressurization using this method is minimal.

conclusions

The optimal methods for diagnosing air leaks in the intake manifold on their own are the use of smoke and spraying the manifold, corrugations, throttles with a thin stream of flammable liquid. Successful diagnostics and smooth roads to everyone!

Suction detection is carried out by inspecting the intake manifold gasket, connections and the body of the hoses. Air suction (cylinder head), ring cuff of injectors is not excluded. Malfunctions of this type occur more often on cars with a long service life. The engine loses power at low or high revs, depending on the type of fuel the machine is running on.

Suction detection is amenable to drivers with years of driving experience and the ability to listen to the engine. The first signs of the presence thereof are starts in the morning or after a long idle time of the car.

Revealing

Consider different ways to detect air leakage into the engine through injectors.

Spraying

Signs of suction are determined by spraying water (you can use a syringe) on the hoses of a running engine. Liquid getting into slots, holes, cracked sleeves or punched gaskets causes a decrease in engine speed.

Another similar method is carried out irrigation of the same segment of nodes with ether, which leads to an increase in revolutions... So, when identifying places of suction, you should carefully monitor the cleanliness of the engine. You can use a vacuum measurement downstream of the throttle to locate the leak. In this case, the removed hose is connected to the throttle valve control.

Video on detecting suction by spraying

Smoke or steam generator

The locations of the duct are identified by the so-called steam generator, capable of detecting any breakdowns, cracks, holes. An analogue of this device, often used by specialists, is a smoke generator.

The device detects leaks in internal cavities where there is air. Closing the throttle valve with a plug, connect it to the intake manifold. Streams of smoke begin to seep through leaks, cracks.

Checking air leakage using a smoke generator

The device also checks for leaks in the exhaust system by plugging the exhaust pipe of the muffler. This is achieved by setting the piston of any cylinder at TDC and belief in valve overlap. In this case, the smoke, passing through the open valves, flows into the exhaust system, revealing the flaws in the density of this area. To this end, the motor starts up and in idle mode, the possible appearance of a hiss, a specific whistle, is heard.

Video on checking air leakage with a steam generator

Possible malfunctions

Knowing the possible areas of leakage, malfunctions are identified:

Without hearing any sounds, you can begin the process of pinching the hose going to the intake manifold.

The clamping operation is performed only with round-nose pliers, in order to avoid damage to the working sleeve.

Squeezing the sleeves of the VUT (vacuum brake booster) or the mixture pressure regulator, stable engine operation is heard. When removing the tool (round-nose pliers), one can feel a drop in speed. This defect indicates the presence of holes or cracks in the tested hose.... Possible malfunctions of the amplifier, adsorber valve.

Diagnostic methods

The failure of the engine to idle is the result of a lean mixture, which is caused by excess air in the fuel line.

This is accompanied by:

• Rusty fuel pipes.
• Fuel hose that has dried out as a result of long-term use and no longer hold the clamps.
• Fuel filter with seal defects.
• Lost exhaust pipes.
• High pressure fuel pump seals.
• Air entering through the manual lever of the fuel pump.
• Fuel pump seals.
• Moral aging of seals.

The first way

Diagnosis of a defect involves disconnecting the fuel pump and feeding it from another vessel (for example, a plastic canister). Independent work will require 3 ÷ 4 liter containers, two transparent hoses, one meter long, a pair of clamps. Observing cleanliness measures, the direct and return fuel lines from the injection pump to transparent tubes are changed, and air is removed from it.

One of the ways to remove suction is considered to be the cleanliness of the place of work and the location of the tank above the fuel pump. It is necessary to unscrew the "return" bolt, through which, according to the principle of a siphon, air exits before the appearance of fuel. The union bolt is returned to its place. By starting the engine for a few minutes, the remaining air is removed.

Video about the diagnosis of the fuel pump for air leaks

Second way

It consists in testing the fuel filter (standard), placing it below the injection pump... The method is focused on determining the suction through the filter. If there is no result, all tubes, tank, hoses are checked. A similar feeding method gives rise to precise malfunctions of a difficult motor start.

The origin of the leakage of the fuel system of vehicles with a diesel engine is justified by atmospheric pressure. It is higher than the pressure that is created when pumping fuel from a car tank. This is due to the replacement of brass fuel lines with rubber, plastic pipes and their connection with clamps. Meanwhile, hoses made of such materials have a shorter service life. Reference is made to the fact that synthetic pipes in the engine compartment heat up, sag, rub, and, when worn out, contribute to air seepage.

Thus, mechanical stress, overheating, the use of cleaning agents capable of softening non-metallic materials and hermetic compounds can be attributed to the root causes of suction.

Video how to eliminate air leakage in a fuel filter on a diesel engine