SORRY FOR OFFTOP!
BUT IN IDEA IT IS USEFUL.
THOSE. THAT NOT EVERYTHING IS THE SAME IN THE CAR!
(the authorship is not mine. This is copyright. Taken from other forums)

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A topic like “it doesn’t pick up speed when I press on the gas?!?!?”

Something must have broken.
Are you aware that you don't have a cable from the gas pedal to the throttle? That is, when you press the gas pedal, the throttle does not open mechanically. Or something like the following might happen:
ECM (engine control module) Guys! Received a digital signal from the throttle pedal that the car should go 53% faster, report it ready!
Front Lambda - tell the injectors not to let gasoline run off, I’m telling you, there’s a LOT of it!
Rear Lambda - Damn! Girlfriend! I have enough of it here, but how do you work there? And the poor catalyst has been rumbling displeasedly lately, although it used to squeak.
ESM - Yes! It's good to talk! Moreover, you are no longer involved in this operation, because if you listen to you, then the car will never accelerate.
Injectors - What are we doing? They opened the door for us, and we let it through. The massmeter is probably lying, but they are slandering us.
Massmeter - Lana! I’ve been working here for 5 years and it’s not easy to slander me, it’s better to ask the candles, they’ve been sentenced more than once in my lifetime.
Candles - Kaneshna! Some counted it, others missed it, but it’s up to us to burn all this nasty stuff! Not only is the gasoline *****, but the compression is also terrible.
Piston rings - What can we do? If only they poured human oil and changed it regularly, but here it’s dripping from above...
Exhaust valves - Correct! The intakes are constantly cooled with gasoline, and we are stuck in the thick of it. So there is no way to help us, and the hydraulics are also hitting as hard as they can, especially in cold weather...
Valve seals - YES! YES!
Intake valves - Yep! We cool ourselves with gasoline. They'll put a phase adjustment on you, then we'll see how you dance.
Hydraulic compensators - Guys! We are holding on here with all our strength! If you try to free a coked spring, you will go wild!
ESM - Calm down! Since you are all such sissies, I’m making an adjustment! Are we going to go? CCM (climate control unit)?
SSM - Leave me a little power, it should be cool in the cabin.
Coolant temperature sensor - Turn it off! We’ll all die here right now, and he’ll still be thinking about nonsense! And tell the fan not to blow it, it’s too hot here.
I'll turn off the ECM - the air conditioner, and wait with the fan. Once you show real numbers, then we’ll add power to it.
VSM (ABS) - Sorry to interfere, but we have a speed dispersion on the front axle. Haldex needs to be strained.
ESM - I’ll figure it out without you! I also found an adviser! Haldex has been knocked out for a long time, and by the way, before his death, he complained that you were clogging up the entire network and not letting signals through to him. I have everything recorded - where, who and with whom! Lana, report back when these speeds level out...
We are working, we are working! ETM (throttle control module), what is our throttle opening angle right now?
ETM - Like 36%...
ESM - What does LIKE mean?
ETM - Well, one sensor shows 38, and the other jumps from 33 to 35, but I still had to adapt, after complaints from Lambda...
ESM - Okay, did you receive a signal about an additional opening of 53%?
ETM - No, nothing came
ESM - How did it not come? I sent it to you half a second ago.
ETM - Well, there is nothing
ESM - Why are you silent then? Then I redirect the analog signal directly to you from the gas pedal, work on it
ETM - Oh... is it too crazy for me to think? I can't think as quickly as you...
ESM - Well, who else? If you messed up your digital connection. By the way, it will be necessary to check in the next work cycle what kind of garbage it is.
So, the ETM is working, we count the air flow, revolutions, load, take into account the temperature... The injectors are moving, the coils are tense... we’re not in a hurry, we’re not in a hurry: 1-2-4-5-3, 1-2-4-5- 3...
Lambdas - FUCKED UP? We've got a flood here!
ESM - Yes? Then I see that the crankshaft sensor reacts strangely. Okay, don't yell! I'll check it in the next 1000 cycles, but you understand that all sorts of road irregularities can affect it. Therefore, unless I make sure of it for sure, I will not officially indicate a misfire!
Brake pedal - STOP!
ESM - Everyone listen! Company stop - one, two...

Do you understand what I mean? It’s unlikely that you can manage here without a specialist. Well, if you yourself want to understand something, then you need to describe everything in more detail, preferably with numbers, and give more detailed information about the car...

Can a faulty fuel pump cause excessive fuel consumption?

Engine Basics

Essentially, an engine is a chemical conversion device. It uses the energy of the fuel to create pressure and heat, which pushes on the pistons to create mechanical energy. This process occurs through combustion when you mix fuel and oxygen in the right proportions and ignite it.

Fuel system

The fuel pump not only pumps fuel, as its name indicates, it also creates pressure in the fuel line. A carburetor engine does not require high pressure, since fuel is supplied to the carburetor's float chamber, and from there to the engine. Fuel injection engines require much higher pressures. Low fuel pressure leads to poor fuel atomization and poor mixture formation, which ultimately reduces engine power. In response to a decrease in engine power, the driver usually gives more gas to compensate for this, and this already leads to an increase in consumption.

Rich and lean mixture

Both rich and lean mixtures cause increased consumption, but for different reasons.
A rich mixture causes increased fuel consumption because more gasoline enters the combustion chamber than can be burned. That is, part of the gasoline simply “flies out the pipe,” into the exhaust in this case.

When the mixture is lean, there is a drop in engine power, which ultimately also leads to an increase in consumption. However, this happens because the driver presses the gas harder to compensate for the lack of power.

Possible causes of malfunction

There are a lot of possible causes of pump malfunction, but let’s try to highlight the main ones:

1. Low quality fuel and the presence of water in it. Water is the enemy of fuel pumps, and it gradually destroys them. Also, water compresses much worse, which also negatively affects the service life of the pump.

2. Clogged fuel filter - a clogged fuel filter creates excessive pressure upstream of the filter, which reduces pump performance and shortens its service life.

3. A malfunction of the fuel pressure regulator, as well as a clogged fuel filter, creates problems for the operation of the pump and shortens its service life.

4. Use of alcohol-containing fuel with pumps not intended for this purpose.

5. Poor quality of the fuel pump; plastic elements inside the pump in cheap pumps often fail.

In our store you can always choose high-quality pumps from time-tested global manufacturers.

High fuel consumption is usually attributed to malfunctions of the car's electronic systems; is this always the case? Now we'll find out...

Let's start with the simplest. How do you measure fuel consumption on your car?? If it’s due to increased gas costs, then it’s stupid (no offense). It is also stupid to measure gasoline consumption using the arrow on the fuel level indicator. First of all, you need to correctly measure the fuel consumption on your car. Of course, the data will still be approximate, but more accurate than the determination “by eye” and “by feel”.

First you need to correctly measure the increased fuel consumption

Fill the fuel tank full. You may not be able to fill gasoline to the top of the neck, because many fuel tanks have a check valve; it does not let fuel out through the filler hole. But the tank needs to be filled as accurately as possible!

Now you need to reset the odometer to zero, and you are ready to go. You need to drive along the highway at an average speed of 90 km/h, without sudden acceleration or braking. The more kilometers you drive, the more accurate the measurement will be.

The most effective means of saving fuel, according to our readers, is the High Efficiency Fuel Saver. The fuel passes through the magnetic field created by the FUELFREE economizer. The fuel molecules are evenly distributed, and its combustion in the engine becomes more efficient. Thereby gasoline consumption(or diesel, whoever drives what) decreases by 30-40%.

After the trip, top up the tank again until it’s full (preferably at the same gas station and from the same nozzle, because they can open differently.) Having topped up the tank until it’s full, you’ll find out how many liters you spent on the train, and you can see the mileage on the odometer. Now we have all the data to find out the consumption.

Divide the number of liters spent by the kilometers traveled and multiply all this by 100. You will get gas mileage per 100 kilometers.

Example: Let's say you drove 86 kilometers and spent 6 liters of gasoline on this trip. We divide 6 by 86, and multiply the resulting figure by 100. We get approximately 6.98 liters. That is, consumption is about 7 liters per hundred.

When taking measurements, keep in mind:

  • What some gas stations may not fill you with
  • The quality of fuel greatly affects the distance traveled
  • Driving style largely determines engine efficiency

Main reasons

In most cases, high fuel consumption is the cause of the malfunction. We will now talk about these faults and consider the reasons for increased fuel consumption.

Fuel rail pressure. Low or high pressure causes high fuel consumption. Check the pressure with a special fuel pressure gauge. The pressure may drop due to a clogged mesh filter on the fuel pump, or due to “fatigue” of the fuel pump itself.

When the pressure in the fuel rail drops below normal, engine power decreases, which forces the driver to press the gas pedal harder, and this causes high fuel consumption. The pressure level for all machines is different, but limits can be distinguished from 2.6 to 4 kPa. These are the average pressure values ​​when the engine is running.

Vehicle voltage. Unstable voltage directly affects the performance of the injectors.

The control unit calculates the injection time, taking into account, among other things, the voltage of the vehicle's on-board network. Check the stability of the output voltage from the generator. This can be done with a multimeter with the engine running.


Oxygen sensor. If it malfunctions or the readings are incorrect, the “check” may not light up, but the consumption will be increased. The fact is that the oxygenator is responsible for optimal regulation of the fuel supply, and if it is faulty, then the consumption will inevitably increase.

Well, if the mileage of your car is more than 100 thousand and the sensor has never been changed, rest assured that it shows incorrectly. Sensor resource is approximately 80,000 kilometers

Coolant temperature sensor. If fuel consumption has increased, then the cause may be DTOZH. When the temperature sensor is lying, the ECU may unreasonably increase the fuel supply, mistakenly thinking that the engine is cold.

The fact is that for a cold engine the mixture is made richer, that is, more gasoline is supplied than to a hot engine.

High speed Idle speed can also cause high consumption. The speed itself may increase due to the throttle position sensor.

Clogged fuel injectors. When the spray quality decreases on clogged injectors, fuel consumption increases significantly. At the same time, acceleration dynamics may drop significantly. The car begins to “stupid”, that is, it accelerates poorly. Sometimes there can be misfires, causing unburned fuel to burn out in the catalyst.

Air filter. A clogged air filter does not allow enough air to enter the cylinders. This causes the mixture to become rich. The oxygen sensor, of course, regulates the composition of the mixture, but as a result, the engine power drops and the driver presses the pedal again, wondering why the car’s gas consumption is high.

If the air filter is heavily clogged, the engine speed may not rise to the possible limit.

Cold engine. If the engine is not warmed up to operating temperature (on Solano and Smile 92 - 98 degrees, on Gili Emgrand and Lifan X60 - 95 degrees.) On a cold engine, the ECU prepares an over-enriched mixture for successful starting. But if the mixture is rich when driving, this will cause severe excess consumption of gasoline. When the engine is overheated, a similar situation occurs.

Camshaft position sensor. In the systems of modern cars, multi-point injection is organized, which is provided by a camshaft sensor. If the sensor fails, the system switches to asynchronous injection, fuel is injected into all cylinders simultaneously, regardless of the phase of the pistons.

Multipoint or multipoint fuel injection is a process in which gasoline is injected into each cylinder separately and only during the intake stroke. With asynchronous injection, fuel is injected into all cylinders simultaneously, but in smaller quantities.

Use of leaded gasoline! At the beginning of the 20th century, Americans came up with a way to increase the octane number of gasoline. They just added tetraethyl lead to it. This type of gasoline is called leaded. The tetraethyl lead additive is very poisonous. In addition, a film of lead settles on the oxygen sensor and “poisons” it. The oxygen sensor begins to lie and fuel consumption constantly increases.

What does it mean? This means that when refueling with gasoline with a higher octane number (95, 98), you run the risk of running into “stuck” fuel. The higher the octane rating, the less fuel detonation (self-ignition during compression). But in this case, more is not always better. Although the 92nd is not immune from fraud, it still has more confidence.

Ignition system. Even if it happens occasionally, fuel consumption will be higher. Gasoline from an idle cylinder is directly thrown into the pipe and, in addition, kills the catalyst. Check the ignition system, wires, modules and spark plugs for possible breakdown.

Mass air flow sensor. Or in some cars intake manifold absolute pressure sensor. The readings of these sensors are used to adjust the injection time and the composition of the fuel-air mixture, so if they do not work correctly, the consumption increases by leaps and bounds.

Question from a reader.

« Hello Sergey and all readers of the siteauto-blogger.ru, I immediately want to say thank you especially for your answers to the readers. So I decided to ask you a question about my VAZ 2114. I have a LUX version with an on-board computer. Lately I have noticed that my fuel consumption has increased. If earlier, about six months ago, the consumption was 7.5 - 8 liters in the city, now, according to the on-board driver, it’s 9.5 - 10.5 liters, although I also drive on the same road to work, and it’s not winter yet! How can we explain this fuel consumption? I noticed that the consumption began to increase after a trip to the south, 1700 there and 1700 back, about 3500 kilometers, maybe the fuel is not of good quality, is something clogged in me? In the morning I noticed that the engine was knocking a little (troiting), could the consumption be related to this? Please give me some advice Sergey, the fuel consumption is just scary lately! I'm waiting for your answer, Arthur."

I'll try to help Arthur. This consumption may depend on several reasons, some you can fix yourself, and some need to be fixed at the station. But everything is in order...

Ignition system

The first reason is the ignition system. Weak points are spark plugs, high-voltage wires and ignition coils.

If you have a lot of mileage and have never changed them, then you just need to replace them. With our “high-quality” fuel, the spark plugs die quickly; on average, I advise you to drive 20–30,000 kilometers with one set; if you have them, then the mileage increases slightly to 30–45,000 kilometers. You shouldn’t skimp on candles, you need to buy proven brands, preferably in official stores or service stations. Even if they are a little more expensive, they will last longer and be of better quality. Your morning detonation may be due to faulty spark plugs, and your fuel consumption may also be due to them.

These are the wires that go from the ignition coils to the spark plugs. They also often fail under the influence of external factors, they can break through and the spark will “go away” - as auto electricians say. That is, the spark plug will not have enough voltage and will not be able to ignite the fuel efficiently, which can also cause the engine to stall and increase fuel consumption. It is quite easy to check broken wires, you need to open the hood at night, start the car and look at the wires, it is advisable to cover yourself with something else so that light does not enter the engine compartment, if a spark runs along any wire, then this wire needs to be urgently replaced, it is advisable to change the entire group of wires. Soon I will write an article on how to check high-voltage wires.

As a rule, an injection car has two or four of them, each responsible for its own two to four cylinders. The coil can also fail, but it is more difficult to determine its malfunction; for this you need to measure the voltage, you need to contact a service station. Due to the ignition coil, the engine will also run rough and there will be increased fuel consumption.

Fuel supply system

The second reason for increased fuel consumption is the fuel supply system. It consists of a fuel pump, filter pipes and a fuel injection mechanism, usually a fuel rail with injectors.

It sits in the tank, is in the interior of the fuel, from our gasoline, the mesh that filters out small and large debris can often become clogged. The fuel pump will strain and supply either a high fuel pressure or a low one, this may give the impression that the engine is throttling, there will also be no traction, the car, as they say, will be “wobbly.” Fuel consumption will also increase. You just need to pull out the fuel pump and clean it. If the fuel pump breaks down completely, your car will simply stop.

If everything is more or less clear with the pipes, they are unlikely to become clogged, then fuel filters are the direct cause of increased fuel consumption. Over time, the fuel filter becomes clogged and needs to be changed. In our realities, replacing the fuel filter should happen every 10 - 20,000 kilometers. If the filter is clogged, then the engine also does not receive the fuel mixture, and the car simply does not drive.

I once wrote that the fuel rail needs to be cleaned, and the more often the better. On my FORD FUSION, after a long mileage, fuel consumption also increased by about 1 - 1.5 liters and traction disappeared. Afterwards, the car became completely different, traction appeared and fuel consumption decreased. Therefore, you need to clean the injector every 50 - 60,000 kilometers, and maybe even earlier, to remove any deposits. You are unlikely to do it yourself; you will need to carry out the work at a service station.

By filtration system, I mean an air filter that filters the air received from the environment. It becomes clogged with dust and dirt, the engine does not receive more air, and consumption increases. There have been cases when just replacing the engine air filter gave fuel savings of 0.5 - 1 liter. It's not very difficult to replace it yourself. It is advisable to change the engine air filter every time you change the engine oil.

Trivial reasons for fuel consumption

There was a case, a friend of mine also had an increase in consumption on our VAZ, he began to eat 1 - 1.5 liters more. Everything has been checked and everything is in order, both the ignition system, fuel supply and air filtration. But the car consumes more and that’s it. It turned out to be simple. The car's rear brake pads were recently changed and the handbrake was tightened almost to the limit, so that with one click up, the car could not be moved. We went to the service station again, loosened the handbrake a little so that with 3-4 clicks the car would lock into place.