Why is my car won’t accelerate but RPMs go up?

The symptoms of a car won’t accelerate but RPMs go up like they used to can occur on many high mileage vehicles. This problem can be caused by a faulty transmission or clogged air filters. This article explains why your car won’t accelerate but the RPMs are rising and how to fix it.

car won't accelerate

Is your car won’t accelerate but RPMs go up?

This is a common problem in high-mileage vehicles, but no major engine problems exist. Some of the causes are actually minor and should be checked first to identify the problem and possibly fix it. Here are some of the most common reasons.

Fuel system problem

If there is a problem with the fuel pump system, it can prevent the engine from getting the right amount of fuel to pump.

This can cause the engine to run unevenly or even stall.

There are several potential fuel system issues that can cause this problem, including a clogged fuel filter, a faulty fuel pump, or a leak in the fuel injector line.

Faulty torque converter

The torque converter converts the mechanical power of the motor into hydraulic power. When a torque converter fails, it can no longer do its job and power cannot flow to the transmission.

Mass air flow sensor clogged or defective

The mass air flow sensor (or flow meter) is located and secured to the intake air cleaner. Since the MAF sensor’s function is to measure the mass of air entering the air intake, a clogged or faulty MAF sensor can send incorrect data to the engine ECU to calculate the air/fuel mixture. A very symptom of a wrong air mass meter is a car that won’t accelerate properly.

Low transmission fluid level (automatic transmission)

A low transmission fluid level is one of the reasons why your car does not accelerate, but the revs increase.

The job of the transmission fluid is to transfer power to the wheels. Power will only flow to the torque converter and not to the engine when the transmission fluid level is low. Quickly check the transmission fluid.

Clutch problems

If the car has a manual transmission, there may be a problem with the clutch. If the clutch does not engage properly, it can cause the engine to spin without actually moving the vehicle. This could be caused by a worn clutch or a leak in the hydraulic system.

Oxygen sensor malfunction

An oxygen sensor is a device whose function is to monitor the exhaust emissions of a vehicle so that it can analyze the air-fuel ratio passing through that vehicle’s throttle body. In short, a car needs the proper amount of fuel in order for the fuel to burn properly in the combustion cylinders so that it can run smoothly and be able to accelerate as needed.

This throttle position sensor sends information about the amount of fuel used to the engine’s computer unit.

If this sensor fails, then that vehicle’s throttle body will not know what air/fuel ratio to use, which can result in a fuel-rich mixture.

This can cause the car to accelerate slowly even with the accelerator gas pedal fully depressed, making it unreliable when needed.

Problem with the ignition system

Another option is a problem with the ignition system. If the spark plugs are dirty or the wires are damaged, this can prevent the spark from igniting the fuel properly. This can lead to misfiring and throttle body instability.

The transmission is no longer connected to the wheels

A broken axle shaft will prevent the internal automatic transmission failure from turning your vehicle’s wheels. This will cause your car to not accelerate, but the revs will rise. You will not feel even the slightest jerk of the car when you turn on the gear.

Throttle body dirty

If your throttle body is dirty, it can cause your car to wobble or stall. The throttle body valve is responsible for regulating the amount of air entering the throttle body. If it is dirty, it can restrict airflow and cause the engine to run unevenly.

Clogged or dirty air filters

Just as a clogged fuel filter does not provide clean fuel to an engine, an air filter provides a vehicle’s engine with clean air to use in the air/fuel mixture that will be sent to the combustion chambers for combustion. If the clogged air filter, the engine will not receive the correct air/fuel mixture, resulting in slow acceleration. Replace the air filter as soon as possible.

Faulty motor control model

Have you exhausted all the options above? You may need an experienced technician to check the engine control unit (ECU). Because computers drive modern vehicles, they can sometimes malfunction due to misuse, or they may need to be updated or rebooted. A good technician knows the best thing to do to fix it.

How are vehicle revolutions measured?

An automobile tachometer is a device that is installed on machines in order to measure engine speed (RPM). It shows the engine speed and is necessary so that the driver does not exceed the maximum allowable engine speed.

The main function is to facilitate the selection of the correct gear. When the arrow approaches the red zone, it is advised to shift to a higher gear. For example, the green zone for a passenger car with a gasoline engine is between 2000 and 5000 RPM. In this range, shifting to a higher gear is desirable in cars with a manual transmission.

Tachometer readings above 5000 RPM are classified as the red zone, you should not bring the arrow to such speeds if you do not have a racing car.

Switching in this range increases fuel consumption.

The tachometer is used for adjusting work at idle. For example, when starting the engine, the speed should be in the range of 800-900 RPM. With a cold start, they are higher – up to 1500 RPM. As the engine warms up, they should drop to the nominal.

If this does not happen, or when the car stands still and does not move in warm weather and the speed exceeds 1000, then there is a problem. For example, the idle speed controller does not work and this will lead to increased fuel consumption.

Also, the tachometer readings at idle should be constant, and not fluctuate from 500 to 1500 RPM.

How does it work?

The principle of operation of a car tachometer is to register the number of pulses that come from sensors. The measured indicators are transformed into certain values. This value can be hours, minutes, seconds, or meters.

It is possible to reset the collected values. The accuracy of the device is conditional, at about 500 RPM, the best electronic devices measure with an accuracy of up to 100 RPM. There are two types of car tachometers – digital and analog with an arrow.

The digital device resembles an electronic scoreboard, which displays the necessary information. It is useful for operations with electronic ignition units or for engine tuning.

Analog – shows the number of engine revolutions by means of an arrow moving along the dial. They are equipped with most serial cars. Its work is carried out electronically. The signal from the shaft is transmitted by wire to the microcircuit, which in turn sets the movement of the arrow along a graduated scale.

Tachometers are distinguished by the method of installation – they can be regular or remote. Remote is used in motorsport. Needed for accurate speed correction when speeds are switched at certain readings.

To do this, they are equipped with a signaling device that will indicate the achievement of a certain speed. The pilot does not even need to constantly read the information from the device, he saw a red flashing light – change gear.

Why do tachometers have different engine speed symbols in cars?

Most cars have been equipped with tachometers for many years, which indicate the number of engine revolutions per minute. A tachometer is required to ensure that drivers do not exceed the maximum engine RPM in each gear. But have you noticed that not all tachometers are the same? No, we are not talking about where the engine speed red zone starts.

In some cars, you may see a different designation of engine speed. For example, in many older cars on the tachometer, you can see a scale of engine speeds of 10, 20, 30, 40, etc. In more modern cars, the engine speed is indicated as numerical values ​​​​1, 2, 3, 4, etc. But why are there two different types of instruments that measure engine speed?

First, let’s look closely at two tachometers with different designations: one of them indicates the number of engine revolutions with the numbers 1, 2, 3, 4, etc., while the others matter \u200b\u200b of 10, 20, 30, 40, etc.

Firstly, these values ​​do not tell the exact number of engine revolutions. Depending on the type of value scale used, the number of revolutions indicated by the tachometer needle must be multiplied by the number that is usually also indicated on the tachometer.

Pay attention to the photo above.

The tachometer with the numbers 1, 2, 3, 4, etc. has the designation X1000, which means that the value indicated by the arrow must be multiplied by 1000. This is how you get the real number of engine revolutions per minute.

When designating the engine speed as 10, 20, 30, 40, etc., you need to multiply the value by 100 (which is indicated by the X100 mark on the tachometer).

But the tachometer for a car … here we see that the value on the tachometer must be multiplied by 1000. The scale marking on the tachometer has the format 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 (other In other words, each number represents 1000 engine revolutions per minute). Got it sorted out. But why do automakers use tachometers with different engine speed scales?

Here the question is more complex. In most cases, today in cars, tachometers have the same designation (X1000). And only sometimes some automakers install tachometers with a different designation (X100) on their cars. Most often, in this way, a car company wants to distinguish its car from the mass of others. Also, in some cases, it can be a kind of design move.

Also, tachometers, designated in the X100 format, were used on older cars, but are sometimes used on modern cars that were not equipped with high-speed engines.

For example, if the car has a maximum engine speed of 4500-5000 RPM, then it makes no sense to use a tachometer with values ​​​​0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 (in X1000 format), so as half of the instrument values ​​will not be used.

What is RPM?

RPM stands for revolutions per minute. This is a measure of how many times the engine’s crankshaft rotates in one minute. The RPM sensor in your car shows how fast the engine is spinning at any given moment.

RPM is important for several reasons. First, it tells you how fast the engine’s crankshaft is spinning and how much power it’s producing. The faster the engine crankshaft rotates, the more power it produces.

Secondly, RPM is important because it affects your car’s gear ratios. Your car has a certain number of gears, and each gear has a different relationship between engine speed and wheel speed.

Finally, RPM is important because it affects your car’s fuel economy. The faster the engine crankshaft rotates, the more fuel it burns. That’s why you’ll get better fuel economy at lower speeds and higher gears.

The revolution of the car engine: what is it for?

So, what exactly does “revving up” a car engine mean? This means that you are literally putting the gas pedal to the metal. You let the engine do what it does best.

Your car picks up speed and makes a signature noise as it revs up. This creates pressure in the motor fluids.

This pressure helps keep your car’s engine lubricated, which means the engine can shift and hold a gear.

Rotation can kill your connecting rod

What is your connecting rod and why is it important? The connecting rod is one of the most important parts of your car’s engine. It connects your car’s crankshaft to its pistons. An increase in the speed of the car engine can damage the connecting rod. If this happens, your engine will fail and you will not be able to drive the vehicle.

It is important to avoid wear before it causes similar damage to the connecting rod and the engine itself.


What does it mean when RPM goes up but car doesn’t accelerate?

If your car won’t accelerate but revs up, it’s often the result of a faulty transmission or clogged air filters rather than an engine problem. If you encounter this problem, please use the services of an auto mechanic to properly diagnose and fix the problem.

When I press the gas pedal it won’t accelerate?

When you step on the gas pedal, the car won’t accelerate fuel filter becomes dirty or clogged, which sometimes prevents fuel from getting to the engine; it could also be related to the fuel pump. A faulty fuel pump is not delivering fuel to the injector. A leaking fuel line can also be the reason why your car won’t accelerate.

Why are my RPMs going so high when I accelerate?

The transmission fluid acts like a coolant and helps transfer power to the transmission through the engine. When the transmission is leaking, the fluid level drops, causing the transmission belt or torque converter to slip, causing the vehicle to spin at a high level.


If your car is not accelerating, but the revs are rising, this could be a sign of several different problems. The most common cause is a failed fuel pump, but it can also be due to a clogged fuel filter, a bad MAF sensor, or a dirty throttle body. If you’re having this problem, it’s best to see a mechanic, so they can diagnose and fix the problem.

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