In the automotive environment, a clear conviction has taken root that driving with a small amount of fuel in the tank, when the minimum residue lamp has already lit up, is harmful to the car. The driver's rumor speaks about this, the instructions for the operation of cars speak about it. At the same time, there is no direct dependence, they say, once I drove with a burning lamp and everything broke, and this seriously complicates the conversation on this topic - it is not known for certain what influences what and what leads to what. There are only observations and theoretical experience. But we nevertheless tried to analyze the situation and understand how really harmful driving on a burning fuel bulb is. Let us consider for this the most popular arguments and confirmations used by the supporters of this point of view.
Overheating of the fuel pump
In modern injection vehicles submersible pumps are used, they are lowered into the tank and "live" among the gasoline. there not only lies, but is located in a special fuel module, which, among other things, includes a plastic anti-drain cup, fuel level and much more. The fuel pump itself is located inside this entire structure, during operation it emits heat, which means it must be cooled. The gas pump does not have additional systems that remove heat (in general, this is a rather simple design), therefore, cooling is done with gasoline - both by what passes through the pump itself and by what floats around in the tank. If there is little fuel in the tank, then heat dissipation deteriorates, the pump overheats may deform and jam. Due to the increased temperature, windings may collapse, electrical connectors may melt, in general, there is little pleasant.
This is the most popular point of view regarding the dangers of driving "on a light bulb", and it is quite logical. True, for some reason it is not taken into account that even when there is little fuel in the tank, the fuel pump does not run dry, it still pumps gasoline through itself. As soon as gasoline runs out, the engine stalls, the pump stops working - a kind of protection from the fool is obtained. Is there enough cooling of the passing gasoline? Purely theoretically - yes, because the gas pump is not a very powerful unit and does not generate very much heat during operation. We managed to find a couple of experiments on the Internet that confirm this point of view. But they, of course, were carried out under sterile conditions, no one measured the temperature in the tank.
Dirt and water at the bottom of the gas tank
Whatever gas stations we fill up at, as the mileage increases, particles of various impurities and water, which forms in the gas tank in the form of condensate, accumulate at the bottom of the gas tank. This is an indisputable fact (in an amicable way, the tank needs to be cleaned periodically), but there is an opinion that when there is little gasoline in the tank, the concentration of "harmful substances" increases and the likelihood of filter clogging increases. A clogged filter does not allow fuel to pass through well, the pump is unstable and breaks down, and the water can go further along fuel system and lead to breakdowns, or even.
Dirt in the gas tank. Photo - drive
On the one hand, it sounds logical, but on the other hand, the design of the fuel intake is so arranged that it always takes gasoline at the very bottom of the tank, and since the "harmful substances" are heavier than fuel, they will still accumulate from below, no matter how much gasoline is in the tank. It was. Clogged fuel module filters are, of course, a problem, but it is not very clear how it is connected with an empty tank and driving on a "light bulb". In addition, deposits appear with time and mileage, but no one says that a burning lamp is harmful only for used cars, new ones are also not recommended to be driven to the last.
Air ingress
Another theory says that at low fuel level the fuel pump periodically "suffices" air, and this harms its work, it is poorly lubricated and rubs "dry" and breaks.
It is also logical and also not everything is clear. The presence of an anti-drain cup allows you to smooth out the fluctuations of the fuel in the tank during turns, acceleration and braking, the gas pump can begin to grab air only when the fuel is almost completely exhausted, but the pump will not work for a long time in this mode, if there is no fuel, the engine will stall, and large there should be no harm.
Here are the top three reasons why driving on low fuel levels is harmful. Each of them has a healthy grain, but none of them allows you to fully theoretically substantiate the problems that can arise from an empty tank. Meanwhile, the opinion of drivers and recommendations of manufacturers still do not arise out of the blue- a very large empirical experience has already been accumulated to notice the connection between low fuel level and the failure of a gas pump.
Not one-time cases, but statistics say that those who constantly drive with an empty tank are more susceptible to pump breakdown. This is especially noticeable on cars with, their owners usually do not fill up a lot, they only need gas to start - the gas pump on such cars, according to statistics, lives less. These statistics are hardly worth ignoring.
At the same time, everything, of course, is individual - cars are operated in different conditions, gas pumps have different designs, the quality of fuel is also different, so it cannot be said for sure that for all cars the consequences of driving are equally negative and lead to the same consequences - someone will break down already after the first "light", and someone drives without problems all their lives, filling the tank with 5-10 liters, simply because the gas pump is very hardy or so the cards lay down.
One thing is certain - a low level of fuel in the tank will definitely not prolong the life of a car, and if you still refuel, then why not just do it more often. You will not lose anything (after all, you still have to pay for fuel), but in which case you will prolong the life of the gas pump. Isn't this reasoning enough to get rid of the habit of driving "on a light bulb"?
To inform the driver about the amount of fuel in the car's tank, on dashboard the fuel level indicator is installed. By itself, it is not particularly noticeable and, in order to exclude the possibility of full consumption of gasoline or diesel fuel, there is an additional warning lamp on the dashboard, indicated by a schematic representation of a gas station.
When the light comes on, the light informs you that there is critically little gasoline in the tank and it will be enough to cover a short distance. The fuel level warning lamp is made so that the driver will notice in advance that there is not enough fuel in the tank and drove in to refuel.
The warning light can be considered a useful addition to the fuel gauge. The fact is that the sensor readings are not always accurate, there are certain errors (due to the configuration of the tank, the position of the car and a number of other factors). Therefore, the sensor can indicate an "empty" tank when it is ¼ or 1/5 full, depending on the volume of the tank (which is 10-15 liters). This can be confusing for the driver, since the sensor needle shows "0" at both 10 liters and 1 liter of petrol in the tank.
Indicator types, operating principles
On cars with carburetor systems, the signal lamp was powered from a potentiometric one, that is, the sensor and the lamp are connected. The principle of operation is very simple - when a certain level of gasoline is reached, the potentiometer slider connected to the float closes the lamp power contacts. At first, the contacts close intermittently (the splashing of gasoline in the tank affects), so the indicator blinks, but with more fuel consumption, the lamp contacts become closed constantly.
In modern cars with injection system power supply sensor and indicator are separated. The signal lamp is powered by its own sensor mounted on the pump housing. The main element of the signal lamp sensor is a thermistor placed in a metal bulb. The principle of operation of the "lamp-sensor" circuit is based on the change in the resistance of the thermistor from the effect of temperature.
Everything works like this: voltage is applied to the thermistor, which is why it heats up. Fuel acts as a coolant for it, it removes heat, maintaining the temperature of the sensor. If the gasoline level falls below this sensor, then the temperature of the thermistor will rise, which leads to a change in its resistance. Due to the change in resistance, the lamp lights up.
The indicator, built on the basis of a thermistor, is good because it is not connected with the fuel level sensor and works independently of it. This makes it possible to notice a decrease in the fuel level even when the fuel sensor is not working.
How long can you drive with a lit light bulb
Now about how much gasoline remains in the tank if the lamp is on and how much it will last for different models this figure is different. On average, car manufacturers set a reserve for 100 km of travel. That is, the light comes on if there are 5 to 10 liters of gasoline left in the tank, depending on the model. But this does not mean that after the warning light comes on, the driver will drive 100 km. The distance that can be traveled on the reserve of gasoline is influenced by the driving style, features road conditions, engine load, etc. That is, one driver will travel 80-90 km on the reserve, and the second will be enough for only 30-40 km. Therefore, you should not hope that you will drive a long distance on the remaining fuel in the tank. When the indicator lights up, you should immediately head towards the gas station.
How to drive if the gasoline light comes on
It so happens that the gasoline light on the dashboard lights up, and you still need to drive a considerable distance to the gas station. And in this case, measures should be taken to ensure that there is enough reserve before refueling. For this you need:
- Choose a path with a minimum number of stops. Keep in mind that 5 liters of gasoline is not enough to start the car and drive to the gas station. A minimum of 10 liters is needed for the pump to be able to fully pump the power system and ensure a stable fuel supply. If there is less gasoline, then the gasoline pump, due to the lack of gasoline, will "drive" the air, because of which the engine will not be able to work stably.
- Pick up speed mode, at which the gasoline consumption is minimal (70-80 km / h).
- Reduce the load on on-board network leaving only the necessary electrical equipment on.
- Close the windows, build on the track behind the truck, this will reduce air resistance to a minimum.
These measures will allow you to drive a greater distance with the remaining fuel.
Than a small amount of gasoline threatens
Note that it is better not to allow the amount of fuel to decrease to the level when the warning light goes off. If for carburetor cars a small amount of fuel does not bear any negative consequences, except that the probability of an unexpected stoppage of movement and a "walk" with a canister to a gas station, then in injection cars this phenomenon is dangerous.
The problem lies in the fact that the fuel pump in such cars is placed in the tank and the fuel for it is the coolant. If there is not enough gasoline, the pump electric motor may fail due to overheating. "Snatching" the air by the pump does not bring anything good either.
Another problem is that when the level is low, the fuel pump pumps fuel “from the bottom” of the tank, where debris and dirt accumulate. This leads to clogging of the fuel inlet filter, which causes the pump to operate under increased load, which increases the likelihood of breakdown.
Video: The light is on, how long will the fuel last?
It would seem, what is there to talk about? The data on the reserve in the fuel tank must be contained in the vehicle owner's manual. Or even simpler: trip computer warns of a low fuel level and tells you how far you can drive to refuel. Not always. Others, instead of specific numbers, give out only dashes, forcing panic even more.
However, the authors of instructions are often limited to general words. For example, "control lamp low level fuel lights up when the fuel tank is almost empty. " This is a quote from the instruction manuals. It also contains even an element of drama: "Running out of fuel can endanger the people in the car." Fearfully...
Than the "light bulb" threatens
Similar exercises are found in the instructions of three bestsellers - Renault Logan, Renault Duster, Lada largus... As a carbon copy: "If the lamp comes on and does not go out, you need to urgently fill the tank with fuel." At the same time, the manual of the related Renault Sandero clearly states - "from the moment the warning light comes on for the first time, you can drive another 50 km."
In the instructions for Lada Vesta there is a mention of a control lamp, and more should be described in the corresponding section, but the link leads nowhere. There is not even such a section as "Car operation". There is "Acquaintance", "Driving", "Leaving" and " Practical advice". On the contrary, Lada 4x4 has specific data (see the table). The same with Chevrolet niva... It looks like a legacy from the Soviet era. But the Japanese and the Europeans (Germans and Czechs) are just as accurate.
Panic aside!
As you can see, in order to find the answer to the question of how long and how far you can drive "on a light bulb", I have studied the operating instructions for the most popular cars in Russia. The data was compiled into a table. Conclusion: the minimum fuel supply that car manufacturers provide us is 5 liters, in most cases about 7 liters. This should be enough for at least 90 kilometers when driving on a suburban highway in a B-class car. So you shouldn't panic when you see a low fuel level lamp or a written warning that the tank is almost empty - unless, of course, you are in the tundra or desert. You will hold out until refueling.
To find out where the nearest one is, look at the navigator map, turn on POI and put a filter by gas station. No navigator - stop to use your smartphone or tablet. A short stop won't hurt. Of course, it is better to find a networked gas station with quality gasoline, but if there is no guarantee that such is nearby, it is better not to risk it and refuel at the first - minimally. When you reach a decent one, fill up a full tank and dilute fuel of questionable quality. And wait a couple of seconds after turning on the ignition before starting the engine: let the pump fill up with normal gasoline.
Car malfunction is unpleasant. A breakdown will become unexpected if you do not follow the vehicle and do not heed the warnings. One of them is a light bulb " Check engine". How to understand what the problem is, what it indicates and what to do if it caught fire.
Button assignment
The dashboard in a car is a way for the driver to monitor the level of gasoline, oil, the state of the engine or other components of the car, which guarantee a comfortable and quiet road movement.
Modern cars are equipped with an indicator necessary for the convenience and comfort of the driver. If earlier the engine malfunction had to be found only visually or by careful listening to the work, today a special light is working. It is designed for the convenience of monitoring the condition of the engine. Ideally, it should light up only when the engine is started and go out after a couple of seconds.
If the light does not go out or lights up when driving, then you should think about malfunctions in the operation of the main component of the car.
How serious the reasons can be
Each signal on the car dashboard is an indicator that the driver must be attentive. When the check engine light comes on, there are several reasons.
- A common cause is gasoline. Due to the additives that unscrupulous manufacturers use in gasoline, the engine does not work properly, it gets clogged. Change the fuel or refuel at a different gas station, and everything works correctly.
- Defective candles.
- Breakage of the ignition coil.
- Triggered oxygen sensor (lambda probe).
- Broken exhaust catalyst.
- Incorrect operation of high voltage conductors.
- Malfunction of the injectors.
- Fuel pump or fuel filter.
It is worth starting the check from the neck cap fuel tank... If it is not fully tightened or defects appear on it, then the light indicates a malfunction of the engine.
Each of the reasons is not very scary, but requires immediate elimination. If you do not pay attention in time and do not diagnose the malfunction, you can lead to complete engine breakdown and the inability of the machine.
The engine is serious, but not necessarily what the job requires overhaul or replacing the engine. The work of the craftsmen is important in any issue related to the diagnosis and repair of the engine. But, if the reason is candles, then the replacement is carried out independently and quickly, without the involvement of masters.
What to do if the light is on
If you see that the engine check light does not burn as it should (it does not go out after starting the engine or burns when driving), then it is worth stopping to diagnose the car. You can do this not immediately, but it is necessary. Remember, if it lights up, this is the reason either go to the service station for diagnostics, or check the engine for faults.
The first thing that can be done when a light bulb comes on is to stop and listen to how the engine works: is there a troit, is there any extraneous noise or knocking. If you hear extraneous sounds, they indicate the cause of the breakdown to an experienced driver. If the cause of the breakdown is not clear to you, the direct road is to the nearest service station.
If the reason for the light bulb lighting is low-quality fuel (this can be determined after diagnostics, after excluding other reasons), then the service technicians will tell you that it is worth changing the type of fuel poured into the car or the place where you are used to refueling.
They also carry out a visual inspection of the engine for cracks, irregularities, leaks. If you yourself find a breakdown, then repairs are carried out according to the reason.
- Oxygen sensor. It is worth replacing it yourself, following the operating instructions for a car of a particular brand. If you do not make a replacement in time, then there will be an excessive consumption of fuel and the catalyst may break down, the replacement of which will be much more expensive.
- Leakage in the fuel tank is the reason for air ingress, which means excessive consumption. It is worth either replacing the lid or achieving tightness by means of gaskets.
- Candles. This is the main element that ensures the ignition of the fuel mixture. If it does not work properly, then the car will refuse to work at all. Replacing candles is not difficult if you are already an experienced driver. You can change either only the candle that has already worked out its own, or all at once, in order to probably already avoid malfunctions in the car. In the store it is worth buying a set of candles just for your car. If you are not sure that you will buy the correct option and can change it, then go to the service station, there are already the necessary parts and the specialists will be able to replace it quickly and affordably. In the matter of candles, it is worth remembering that old-style cars need to be replaced every 20,000 km, and if the car is new, then on the same candles it can travel up to 150,000 km. If you change the candles on time according to the requirements technical operation your car, then you can avoid damage to the catalyst and improve engine performance.
- Replacing the MAF sensor. This part regulates the amount of air that is required for rapid ignition. When it is faulty, it means excessive fuel consumption, an increased amount of carbon dioxide in the exhaust, poor acceleration, and a decrease in engine power. Most often, the breakdown is associated with an incorrectly installed air filter or the filter has already expired. When it comes to changing a sensor, the costs are related to the price of the sensor itself, but the replacement service in the service is not so expensive, because it does not require a lot of time and is simple in technology. Regular filter replacement is a guarantee of long-term sensor performance.
Nuances in the work of the "Check engine" light
The check engine light on the dashboard appeared in the early 90s. but then the work of the sensor was aimed only at monitoring the operation of the carburetor. That is, the light came on when:
- There was a blockage;
- The combustible mixture was prepared incorrectly for engine operation, etc.
Today, the work of a light bulb is much wider. Carburetors in cars of the new model no longer exist. Instead, injectors are installed. It is in connection with this novelty in the car that the light bulb shows not only the wrong mixture. Thanks to her, the driver learns about:
- Interruptions in work;
- Ignition problems;
- Poor gear shifting and more.
See what else a burning check engine light may indicate (video)
Outcome
Thus, thanks to such a light bulb on the panel, it is possible to control almost every element of the engine, its condition and performance.
The engine control light on the driver's dash is a status indicator. If it does not burn according to the rules, then you should pay attention to this and go for a diagnosis. Timely elimination of breakdowns is a guarantee of safety and comfort on the road. Attentiveness to your car will exclude breakdown at the most inopportune moment.
