Every motorist knows that if the car does not start the first time, it will be much more difficult for it from the second and third times, but not everyone knows that the problem at such minutes often lies not in a dead battery, but in flooded spark plugs. What floods them, why and what to do in such situations, this article will tell.
We define what this means and why is it happening?
It's no secret that an internal combustion engine is a rather complex device in which several sequential processes take place. The first process is the supply of a fuel-air mixture, during which the fuel is mixed with air and enters the engine cylinders. The second is the compression of the named mixture by the cylinders, by raising the piston as high as possible with the valves closed. The third is ignition: a spark is supplied to the cylinders, where the fuel-air mixture is under pressure, provoking a mini-explosion, igniting the said mixture and moving the piston downward. The fourth process is the release of exhaust gases through the piston and valves into the gas outlet system.
This is how the internal combustion engine operates under normal conditions, however, in winter (in the cold), malfunctions can occur in this sequential cycle.
Due to the fact that cold air is much more enriched with oxygen than warm air, a larger volume of fuel is required to ignite it. The ECU knows about this and gives the appropriate command to the injectors. Those, in turn, send the adjusted upward amount of fuel into the combustion chamber, where at this time the starter tries to simultaneously create good compression and give a spark to generate a flash. Taking into account the poor quality of gasoline at our filling stations and the presence of some wear and tear of parts (we are not talking about new cars here, because the compression in them is ideal, so the question is: the candles are flooded, what to do? – just not worth it), he does not always succeed in doing it well. As a result, the mixture does not ignite, and the fuel supplied to create a chemical reaction floods the candles, completely paralyzing their work. This can happen for only 2 reasons:
- due to a too simple and already outdated injection system in carburetor engines, in which there is no measure of fuel supply (even if the car does not start, the system will continue to "pour" gasoline in the amount "prescribed" in the settings), as well as its incorrect settings;
- (found on a carburetor car and on an injector) due to a weak battery, which at low temperatures is simply not able to create the required voltage to ignite a spark.
An unsuccessful engine start can upset any car owner. Often the cause of the detected failure is the wet electrodes of the spark plug of a gasoline engine. Due to the complexity of diagnostics, the search for an answer to the question of why the spark plugs are flooded usually becomes a “blind” search.
A detailed analysis of the processes occurring in the engine cylinder helps to correctly understand the reasons for this phenomenon. In this case, it is necessary to take into account the type of fuel system and ignition, the season and the characteristics of the spark element.
How do flooded candles work?
Wet spark plug electrodes appear due to the ingress of only two liquids on their surface - gasoline or oil. In the first case, we boldly call the fuel intake system "guilty", and the reasons for the oiling of the electrodes are different.
The problem of flooding spark plugs is typical for engines of any system. Both carburetor and fuel injection engines suffer. Regardless of the source of failure, the failure of a plug to function normally is expressed as follows:
- Refusal to start the motor... The malfunction is more common for a cold engine, but it also occurs with the engine when trying to restart it.
- The appearance of a persistent smell of unburned fuel... Gasoline-air mixture, when it enters the cylinder cavity, does not ignite and is thrown into the exhaust system.
- When inspecting an unscrewed candle, damp electrodes or dark carbon deposits are observed.
It is easy to determine, without unscrewing the filled candle, by the absence of pickups when scrolling the engine crankshaft.
Before deciding what to do with the malfunction of the ignition system, it is required to determine the nature of the malfunction and eliminate the source.
Reasons for constantly flooded candles
Wet electrodes are faults in two main ways. In the first case, the candles will be poured in case of malfunction of the power supply and ignition systems. In the second situation, the parts of the cylinder-piston group are to blame, when oil particles contaminate the electrodes.
The process of mixture formation in the cylinders, taking into account the cold start, is carried out according to the following algorithm. The engine control unit takes into account the outside temperature and the cold state of the engine. Taking into account the oxygen concentration, a decision is made to increase the supply to the injector. There is a deliberate enrichment of the working mixture. Under normal conditions, the engine will start without gaps. But under certain circumstances, the candles will flood without forming a spark:
- Increased clearances of parts of the cylinder-piston group... With a cold engine, this leads to a decrease in compression, which does not contribute to the ignition of the mixture. The factor should not be considered if the problem is identified on a separate cylinder.
- Poor fuel quality... Timely vaporization of gasoline is possible with its high quality and in the absence of dilution with moist air condensate.
- Uncertain scrolling of the crankshaft by the starter with thickened oil or a weak battery... In this case, an insufficient spark is generated, which does not provide sufficient impulse to ignite the mixture.
All of these factors make up the causes of misfire. Sometimes the factors act as a whole, but it is better to diagnose them separately.
The reason is the candle
It is possible that the described factors do not affect the source of the spark in the cylinder. If she still pours gasoline on the candles, she herself often becomes the culprit. There are two possible situations here:
- Sparking problem... As a result of the operation of the crank mechanism, the formation of pressure is possible, which cannot be overcome during the formation of a spark. This results from a large gap, insufficient current.
- Leakage current. It occurs in worn-out products when the insulating properties of the spark body are violated, and the current flows directly to the ground.
If the owner of the car does not know how to properly test the spark plug, it is worth contacting a specialized service to test the product at the stand.
When replacing candles due to their failure, pay attention to high-quality and durable products. To answer the question which spark plugs are better, follow these rules:
- compliance with nominal sizes;
- selection of a spark source according to the degree of motor boost;
- material of electrodes with a long service life.
If it is impossible to independently determine all the parameters, do not hesitate to consult with the seller.
Sprinkles electrodes with oil
Another common cause of electrode flooding is related to the engine lubrication system. Such a malfunction will befall both the injector and the carburetor engine. It is appropriate to exclude from this list only two-stroke motors, where a separate lubrication system does not exist.
When determining the source of "oiling" of the electrodes, the area of contamination should be considered. In this case, the following circumstances are taken into account:
- Bottom plug contamination... The reason is the wear of the piston system or even damage to the oil scraper ring.
- Accumulation of grease at the top... The appearance of oil is possible due to damage to the valve cover gasket or valve seals.
The causes of damage to engine elements lie in engine overheating, operation with an overestimated oil level, clogging of the ventilation duct of the engine crankcase. A detailed diagnosis of the reasons for the refusal should be entrusted to experienced minders.
Other engine malfunctions
Among other reasons for the malfunction of the candle, there are:
- violation of fuel injection pressure and lack of fine spray;
- malfunction of the sensors of the electronic control unit;
- clogged fuel injectors and malfunctioning of the high pressure pump.
Usually, these reasons are clarified after the first negative results of the primary diagnosis. In this case, doubts like “what to do” are resolved by a comprehensive diagnostics of the operation of the internal combustion engine systems.
Directions of elimination of the situation
When candles are filled with gasoline, it is usually sufficient to dry them. It is enough to unscrew them from the seat and turn the engine to purge the cylinders with air for 10-15 seconds, and treat the electrodes with a stream of hot air.
The closed blowdown method can also be used. Here you need to know how to use the controls correctly. With the gas pedal fully depressed, the crankshaft is scrolled. Abundant streams of air also dry out the candles. On subsequent release of gas, the incoming gasoline ignites.
With regularly working unstable candles, we choose further actions based on the causes of the malfunction. It is better to replace damaged spark plugs and repair a serious engine malfunction.
When candles are poured on an injection engine, then, as a rule, problems arise with starting it. For example, in the evening you returned from work, parked your car and calmly walked home.
Morning comes, you have to go to work, and the car refuses to start. And the starter turns, but there are no signs of even attempts to ignite the fuel composition.
Therefore, a modern car enthusiast must be ready for any surprises and be able to react to them correctly.
By the way, this phenomenon is typical for any of the types of fuel systems (carburetor, injection - this is not essential).
In most cases, the trouble occurs in winter, when it is frosty outside. In the warm season, fueling the spark plugs on the injector occurs much less frequently.
So what do you do?
Main reasons
First, let's look at the main reasons for this phenomenon. Surprisingly, but the main source of problems in this case is the car's ECU and the features of its firmware.
When the street is "minus", the system tries to create certain conditions for the fuel mixture. It is no secret that oxygen volumes are much higher in frosty air.
So it turns out that the ECU sends an order to the injectors to give a larger volume of fuel.
Naturally, "orders are not discussed" and the injectors increase the amount of gasoline injected.
What's next?
The accumulator undergoes colossal loads in cold weather and may not produce the required voltage level (and there is no guarantee that it is new).
You turn the ignition key, the injectors deliver the required volume of gasoline to the combustion chamber, the starter does everything possible to crank the crankshaft and create a sufficient level of compression in the engine.
The candle is trying to work at the same time.
That's right, but the quality of domestic fuel is far from being at the best level.
At the same time, in cold conditions (and even not on a new car), it is not always possible to achieve ideal compression.
The injectors have done their job, the spark plugs spark every other time, and the compression level is too low. The result is flooded candles.
How to proceed?
If it floods the candles on the injector, you can go in two ways.
The first is the simplest... Unscrew the candles and dry them well. To "drive" the engine, you need to turn the starter for at least 8-12 seconds. At the end of the work, the candles can be returned to their place and try to start the engine.
Method two... Start-up in the so-called "purge mode".
What to do in this case?
Press down on the accelerator pedal as far as it will go and turn the key in the ignition lock.
Crank the starter for 8-10 seconds. At the end of this time, the pedal can be returned to its original position.
In most cases, the engine will start.
The peculiarity of this method is that when the gas is fully pressed, the fuel supply to the engine is shut off, and the candles themselves are blown exclusively with air.
If the engine still does not start, then it is necessary to dry the candles.
How to do it?
As tools, you can use a regular toothbrush (or metal brush) and a hair dryer (for more effective drying).
If it is possible to take the candles home, then you can "ignite" them in the oven or directly on the stoves. But this method is only temporary.
If the candles have already departed their resource, then it is better to simply change them.
It happens that almost every day he floods the candles on the injector. In such a situation, it is necessary to carry out a complete check of the elements - for the presence of a spark outlet, the cleanliness of the nozzles, the quality of the spark, and so on.
How to act to rule out trouble
- firstly, you need to monitor the battery charge level and periodically (this is especially true for winter);
- secondly, monitor the serviceability and if any problems arise, do not be lazy to go to the diagnostics;
- thirdly, only the best quality, which is suitable for use in winter;
- fourthly, promptly change and inspect high-voltage wires for the fact of their possible failure;
- fifth, adjust and. It's easy to do - add one of the special formulations that are sold in stores to the tank;
- sixth, use high quality. To do this, refuel at proven gas stations.
Remember that during the cold season, the engine does not like small trips at low speeds.
The problem of filling the injector plugs can also be a faulty operation of the bypass valve in the fuel rail. To check if the bypass valve is working, measure the fuel pressure in the rail. The fuel supply must be strictly under the pressure specified for a particular engine. If the fuel is supplied with an underestimated or overstated pressure, then the candles are flooded.
Injectors are also subject to diagnosis. You should also diagnose the electronic engine control system (ECM) sensor. Since the control unit decides to enrich the mixture or lean it out, if, for example, the coolant temperature sensor (DTOZH) does not work, the control unit receives incorrect temperature data and incorrectly distributes the fuel supply, the injectors begin to overflow fuel. It is also possible that the control unit itself has gone out of service.
Spark plugs have been doused with engine oil.
We have already seen that spark plugs can be filled with gasoline or engine oil in carburetor engines and injectors.
If you find that the candles are filled with engine oil, you need to look at exactly where the oil is located.
If the oil is in the upper part of the spark plug, at the beginning of the insulator, then, most likely, the problem is in the valve cover gasket, oil seals.
If the threads of the spark plug and the electrode are filled with oil, then, most likely, the cylinder-piston pair has worn out, as well as the oil scraper piston rings are out of order. All this leads to the formation of soot, varnish, sludge, coke. Then you have to cleanse, do.
What to do if candles are flooded.
How to start a car if the engine spark plugs are flooded. For the case when the candles are wet from gasoline in the injection engine, unscrew the candles, hold them with pliers over the fire (dry), turn the starter without installed candles for about 10 seconds to ventilate the pistons. After that, the candles are twisted and, as a rule, the car will start.
How to dry cylinders without unscrewing the spark plugs in the injector
Dry the cylinders in this order:
- The gas pedal is squeezed all the way to the maximum.
- Turn the ignition key and turn the starter for about 10 seconds.
- Release the gas pedal.
If the gas pedal is pressed, the throttle valve is open, due to which there is air circulation and the candles are dried.
In this non-tricky way, you can start an injection car after filling the candles with gasoline.
If the method of drying without dismantling the candles does not help, then you will have to dry the candles by hand. Manual cleaning is better, since the electrode itself can also be quickly cleaned of carbon deposits and heated over a fire, and check the gap.
Spark plugs are not expensive, those who do not want to mess around and clean them, buy new ones that are appropriate for a given engine.
The service life of spark plugs is from 15 to 25 thousand kilometers.
If simple small-scale repairs and simple actions to eliminate this cause do not help, then it is necessary to carry out in-depth diagnostics: check the ignition system, ignition coils, injectors, temperature sensor, Hall sensor.
In the video, the solution to the question: why the injector does not start in frost.
In addition to the already named main reason for filling candles, there may be others:
- At the start, the crankshaft turns slowly (we repair the crankshaft).
- The malfunction lies in the valve stem seals that let oil through (we change the valve stem seals).
- The nozzle is clogged, but it continues to supply gasoline, and the candles are filled with it (we clean the injector).
- Water appears in gasoline (this happens most often in winter, we choose the right brand of gasoline - "winter" or "summer").
The latter case is also quite common, especially at sub-zero air temperatures. This is due to the fact that gasoline, which has low volatility, has a poor combination with cold air, so the fuel mixture turns out to be heterogeneous and begins to fill the spark plug elements.
What to do if it pours candles on the VAZ-2114 injector
Experts advise, if a similar problem is found, to initially check the correct formation of a spark on all candles. To do this, you will have to examine each of them:
- turn off the ignition;
- remove the plastic engine cover;
- disconnect one of the battery terminals;
- remove high-voltage connectors (for this you just need to pull them out by the rubber caps);
- dismantle each candle using a special spanner wrench (also called a "candle" wrench);
- close the candle well (this should prevent dust from entering it).
As soon as the candle is in our hands, we immediately inspect it for carbon deposits. After that, the distances between the spark plug contacts are checked - the digital values must correspond to the part passport.
If carbon deposits are noticed on the spark plug element, then it must be removed without fail. This can be done with a brush - either a toothbrush or a metal cleaner. After cleaning, put in place, after drying it. To do this, just use a regular hair dryer.
Another way to dry the spark plug elements directly in the engine, without unscrewing them, is to purge the cylinders from the unburned fuel mixture:
- remove the block of wires from the ignition module (it is necessary for reinsurance so that the module does not burn out when the engine is cranking);
- include a starter;
- sink the gas pedal;
- twist the starter for 7 minutes.
As a result of such actions, air is sucked in through the ramp. If it is noticed that the candle is in a faulty condition, then it is simply replaced with a new one. Of course, it takes a lot of time to check, clean and dry old candles every time. Therefore, experts advise to buy a set of new candles and simply replace the filled ones.
When it's not about the spark plugs, but about the carburetor or engine, a completely different repair will be required.
Candle cleaning prophylaxis
Experts recommend a simple preventive procedure for cleaning the injection system and candles, which can be carried out monthly. To do this, you should:
- Drive onto the road with a distance of 100 kilometers.
- Drive the car at a speed of 120 km / h.
Due to the strong pressure exerted, the injector system goes into self-cleaning mode.
