Every motorist knows perfectly well what a throttle valve is and what place it occupies under the hood of a car. During operation, this part takes two positions - it can be closed or open. And so that the driver knows exactly what position the part is in at a particular moment, there is a special position sensor throttle valve. Let's try to understand the device, the causes of the malfunction and methods of repairing the latter.

1 How the throttle position sensor works and why it breaks

To understand how the most popular non-contact position sensor works, we need to understand the design of the part. This item refers to resistive devices. If we disassemble the sensor device, then inside we can find a movable slider that moves along a track in the form of a horseshoe or arc. The device operates due to the influence of magnetic waves that are created using air currents. It is precisely because of this operating principle this part called a non-contact sensor.

Let's begin with a review of the most common breakdowns of such important element car. Malfunctions often occur due to wear of the resistive layer on the tracks along which the slider moves. Such breakdowns occur with non-contact sensors and other types of parts. Often wear occurs in the area of ​​the track where the slider begins its movement. This malfunction clearly visible when viewing the element visually.

Another type of throttle position sensors, powered by electrical supply, very often ceases to perform its functions due to frayed wires. In most cases, such parts operate on a voltage of 5V.

If the sensor is faulty, then when measuring the indicator you will see that the part receives power of 0.3–0.5V. In this case, in the fully open position of the damper, the sensor will operate on a voltage of 3.2–4.7V.

Some vehicle models are equipped with sensors with inverse output characteristics. When the throttle is closed, such details will show maximum voltage. The more the damper opens, the lower the power supply will be. Very often, drivers confuse this feature of the throttle position sensor with a breakdown. To make sure your guesses are correct, you need to study technical certificate vehicle, where the sensor type is indicated. To test such models, auto power must be determined not with one, but with two potentiometers. One device is designed to determine the direct inverse characteristic, and the second will show the inverse indicator at the output.

2 The first symptoms of a breakdown of the throttle position sensor

The fact that the throttle position sensor is broken can be determined by every car owner. To do this, you need to know about the main symptoms of part failure. These include:

• The car engine is unstable or stalls Idling;
• when you press the accelerator pedal, the car randomly revs up the gas, or, conversely, stalls;
• the car “fails” in 1st–3rd gears.

The last type of malfunction is very common when execution fails. This problem is also encountered by drivers who replaced the original sensor with a low-quality analogue. Non-original parts are characterized by the fact that they are almost completely dependent on temperature. This means that the more the throttle position sensor housing heats up, the more often the element’s power output changes. For example, if the sensor shows an output voltage of one value when the engine is not running, then as the engine heats up this indicator will rapidly increase. At the same time, the ECU will not have time to respond to an increase in sensor voltage, which directly affects the operation of the car when shifting gears.

To eliminate the malfunction for a while, the driver just needs to turn off the ignition and then immediately start the engine again. In this case, the ECU will save the last indicator of the sensor power supply as if the throttle was closed. When the driver starts the car again, the ECU will work more stably, without “sinking” the car when changing gears. But do not forget that this is just temporary help for the car. And as soon as you discover a malfunction, immediately go to the nearest car service center.

3 Repairing the throttle position sensor at home

Above we looked at the most common causes of throttle position sensor failure. Since most often the resistive layer in the design of a part wears out, repairing this particular part of the device is worth considering in more detail. Very often, drivers who have already encountered such a problem wonder about methods to solve it. The answer is very simple - it is impossible to do this at home. The only solution is to replace the damper position sensor completely. To do this, you need to remove the faulty device by unscrewing the fasteners and disconnecting it from the power supply and from the engine ECU. After this, we install a new sensor, connect it first to the ECU, and only then turn on the power. It is very important to install new part exactly in that order. There is no need to make any additional settings.

The operation of any injection engine is controlled by electronics in the form of an ECU (electronic control unit), the operation of which is based on the readings of a group of sensors that monitor the condition various systems and engine components.

One of this group of sensors is the TPS. It is installed directly on the damper axis and monitors the slightest change in its position.

In turn, the throttle valve serves to change the air supply to the engine to form the optimal composition of the air-fuel mixture, and the controller needs exactly this information about the amount of incoming air.

Based on data on the amount of air supplied, in this moment time, the ECU calculates the fuel rate to create the optimal mixture for its complete combustion in the engine cylinders. This in turn will guarantee full power output from the power unit and its economical operation.

How does the sensor work?

The position sensor is a conventional potentiometer ( variable resistor, it works like, for example, a sound volume control in radio equipment) with a sliding contact, due to which the voltage at the output of the device changes from zero to maximum.

Any potentiometer is equipped with three terminals, two connected to the ends of the winding, and one to the moving contact. One of the terminals is used to supply voltage, the second is “ground” and the third is used to communicate with the control unit.

Usually the winding is made in the form of a flat spiral with equal distances between the turns, or it can be plastic film with sputtering of a resistive layer in the form of one or two tracks.

Principle of operation

When the throttle valve is closed, there is no signal from the sensor to the control unit and the voltage has background values. As the damper opens to a certain angle, the voltage increases, up to a maximum when it is fully opened.

Each damper position corresponds to a certain voltage value, by which the controller determines the amount of incoming air in order to command the injectors to supply a certain dose of fuel.
If the ECU receives a signal from the sensor that the damper is completely closed, it issues a command to open the IAC to supply air through the bypass channel.

What types of malfunctions occur?

In most cases, sensor failure is caused by wear of the spiral turns, track spraying or the working part of the runner. The part of the track where the slider moves most often is subject to wear, which corresponds to the position of the gas pedal while driving, when the engine is running at a certain speed.

Sensor failure can also be caused by oxidation of the contacts or dirt getting into the connection.

Inadequate sensor readings can also be caused by sticking of the throttle valve due to accumulated dirt and carbon deposits.

Sensor malfunctions expressed in power plant, during acceleration, a drop in power and stopping the engine after removing your foot from the accelerator pedal.

How to check the operation of the sensor?

You will need a multimeter to check.

The tester switches to voltmeter mode. The chip is removed from the sensor and with the engine running, the voltage between the power and ground terminals is measured. The device should show about 5V (+/-);

The ignition is turned off and the tester is set to check the resistance. Then, with the damper completely closed, the resistance is measured between the sensor terminals: “ground” and the contact for the control unit. The device should show 0.8-1.2 kOhm;

If the test reveals that the sensor is faulty, it must be replaced.

Replacing TPS

Remove the power supply from the sensor;

Release the fastening bolts;

Carefully connect the end of the damper shaft to the recess in the sensor;

Install the fastening screws;

Reinstall the connector.

After replacement it is necessary reset error from ECU memory. To do this, remove the battery terminals to reset the memory.

On some brands of cars, after installing the sensor, it must also be adjusted.

Adjustment procedure:

Close the damper completely;

Connect the tester probes (on the voltmeter scale) to the engine ground and the sensor output;

Then, having loosened the fastening screws, turn the sensor until the moment when the device shows the most low voltage(0 V, at ideal ratio, but “live” can show a little more);

Having achieved minimum value voltmeter, tighten the mounting bolts.

In case of increased engine speed after adjustment, it is necessary to familiarize the ECU with the characteristics of the new sensor.

For this:

For 15-20 minutes, remove both terminals from the battery;

Replace the terminals and make sure that the throttle valve is completely closed;

Turn on the ignition for 10-15 seconds without starting the engine and turn off;

Wait 15-20 seconds so that the ECU can “remember” the data of the new sensor.

Average cost of TPD, for various models car, is about 1500 rubles.

The throttle position sensor (TPS) is an electronic device that provides a relationship between the throttle valve angle and voltage, which regulates the level of fuel and air supplied to the cylinders. This element is used in engines with fuel injection.

The design of the sensor is quite simple: a potentiometer with three terminals is rigidly attached to the throttle valve. One of the terminals supplies the operating voltage, the second is connected to ground, and the third allows the engine control unit to record the received data for further processing.

The operating principle of the throttle position sensor can be understood based on its design. A closed throttle valve should not produce a signal, so the voltage is kept within background levels. When the throttle valve is opened, the voltage level increases up to maximum value, if the damper opens completely.

The signal sent by the TPS makes it possible to monitor the current position of the throttle valve, and the rate of change of this signal sends information about the dynamics of the gas pedal to the engine control unit. The engine control unit receives a signal about the voltage level on the potentiometer and promptly makes changes to the operation power unit, regulating the fuel supply and the moment of spark occurrence.

When starting the engine, the TPS determines the degree of opening of the damper. If it is open more than ¾, then the controller starts purging the power unit. The closed position allows the idle air control to be activated, which allows air to be supplied to the engine through a bypass channel.

Signs of a malfunctioning throttle position sensor

It is worth immediately noting that the signs that appear when a faulty TPS can be interpreted in different ways. Sometimes inexperienced drivers, when there is a lack of speed, immediately change the throttle position sensor, although it could well be in good working order. In general, there is no need to rush to replace this element - first you need to make sure that it was its malfunction that caused the poor functioning of the engine.

It is quite easy to notice signs of malfunctions in the throttle position sensor, since there are many of them:

1. Rise or instability idle speed engine.
2. Lack of revolutions when engaging neutral gear, due to which the engine constantly stalls.
3. When driving, there are noticeable jerks and a noticeable drop in dynamics.
4. On dashboard the light came on " Check Engine».
5. The engine cannot be started the first time, and during further operation there is a slight “uncertainty” of the motor.
6. Increased fuel consumption.
7. A noticeable drop in engine power at any speed.

DPZD: side view

Each of these signs is unpleasant in itself, and when they begin to appear synchronously and with enviable consistency, this is a clear sign that it is necessary to check the engine, including the throttle position sensor (this element quite often fails).

A faulty TPS often causes the problems described above, and its condition must be carefully monitored.

How to check the throttle position sensor

Symptoms faulty sensor are quite vague and can indicate the occurrence of a variety of problems. To accurately verify that the TPS is faulty, it is necessary to diagnose it.

Checking the sensor is quite simple, and the only equipment you need is a voltmeter. The verification algorithm will look like this:

1. First you need to turn on the ignition. Next, using a voltmeter, the voltage level between the slider and the negative terminal is measured. The voltmeter needle should not move above 0.7W. Otherwise, we can conclude that there is a malfunction.

2. If the previous step was completed successfully, then it is necessary, without disconnecting the voltmeter, to open the throttle valve all the way. The voltage should rise above 4 V. The operating voltage with the damper fully open usually fluctuates within 5 V, but small deviations are quite possible even with a working sensor.

3. The following action must be carried out with the ignition off. To check, remove the connector and check the resistance between the slider and any of the terminals.

4. When turning the movable sector, you need to carefully monitor the movements of the voltmeter needle. Smooth and unhurried movement suggests that the throttle position sensor is in order. Jerking or chaotic movements of the needle are a sure sign that the TPS needs to be replaced.

Throttle position sensor: possible malfunctions

The throttle position sensor has a fairly simple device, but even taking this into account, it contains elements that can fail due to wear or sudden overload. Among the most common TPS problems The following can be included:

1. Abrasion of the base coating at the initial segment of the slider movement. An erased resistive base always causes a TPS malfunction. As the slider moves, the voltage supplied to the engine control unit should increase - but this does not happen due to the lack of resistance. As a result, malfunctions occur, including failure of the engine control unit.

2. Malfunction of any tip. The slightest problem often leads to a host of other problems. In this case, damage to one tip leads to burrs appearing on the lining. They, in turn, disable the remaining tips. In this case, the contacts can sometimes continue to work, but not for long, and the wear of the substrate will be much higher than under normal conditions. In any case, with such a malfunction, the resistive layer and the slider do not contact, thereby rendering the power unit inoperable.

3. Failure of the slider. Sometimes the slider itself causes a malfunction in the throttle position sensor. As a rule, this structural element wears out over time or begins to move away from the correct trajectory, resulting in a malfunction.

To troubleshoot the TPS, you should first figure out whether minor repairs can be done, or whether it will be much easier to replace the entire structure.

Despite the simplicity of the throttle position sensor, repairing it is quite difficult and not very profitable. You can clean the contacts or bend them, but this solution is more like half measures - it will be much easier to purchase and install a new sensor.

Video: what is TPS, causes of malfunction and solution

Conclusion

We have determined where the throttle position sensor is located and what it is. The throttle position sensor is a small but proud element electronic system engine control, if it malfunctions, a lot of problems arise, including the impossibility of starting the power unit. The simplicity of the design in most cases does not provide sufficient space for repairing the TPS, but the low cost of this element eliminates the need for repairs, allowing you to simply replace the defective part.

Release injection engines contributed to the emergence of various electronic devices. Including sensors that collect information regarding the performance of a particular system.

Thus, control is taken over by an electronic unit that monitors the performance of all engine systems using these sensors. The malfunction of even a minor part leads to undesirable consequences in the operation of the entire car. One such part is the throttle position sensor.

TPDZ - what is it?

The throttle position sensor signals to the controller what position the throttle valve is in when the accelerator pedal is pressed.

This device allows the controller to more accurately dose and supply the fuel mixture. If the sensor malfunctions, the information is transmitted to the controller in a distorted form. This may cause the engine to malfunction and result in excessive fuel consumption.

The controller registers the location of the throttle valve by changes in voltage. A 0.7 V signal forces the controller to switch to idle mode. If the voltage is less than 0.7 V, this indicates that the damper is completely closed. And if the voltage is about or more than 4 V, then the damper is fully open.

Where is he located

In order to be able to check the TPS if necessary, you need to know where it is located. Its location is on the throttle body and is connected to its axis. There is a special groove on the axis, for which a cross-shaped socket is provided on the sensor.

The sensor housing is secured to the throttle body using bolts. The sensor is installed on cars with injection engines.

Signs of a malfunction of the TPS

Any part fails sooner or later, as evidenced by characteristic features. TPS is no exception.

Typical signs of a malfunctioning throttle position sensor may include:

• the engine idles at high speed;
• clearly observed high consumption fuel;
• on neutral gear the engine stalls;
• the car jerks when accelerating;
• sometimes the Check Engine indicator may light up and stay on for a long time;
• The engine starts with difficulty.

All these signs indicate that the TPS is faulty and, therefore, requires immediate replacement of the part.

Video - some signs of a malfunctioning throttle position sensor:

How to check

If some signs of a malfunction of the TPS are detected, but it is completely unclear what they indicate, then you can independently check its performance.

Typically, when there is a problem with the TPS, the Check Engine light on the dashboard lights up. Therefore, first you should start the engine and if the indicator does not light up, you need to crawl under the hood to the sensor itself.

To check its functionality, it is not necessary to remove it; everything can be done on site. To do this, you need to connect two wires of the multimeter to terminals B and C of the sensor. The corresponding marking is available.

After this, you can start smoothly, slowly turning the throttle using the drive sector. If the sensor is working properly, the device readings should also change smoothly without sudden jumps. Typically from 2 to 8 kOhm. Resistance measurements should be made with the engine turned off.

Video - checking TPS:

Now you should measure the voltage. To do this, first connect the negative of the multimeter to the engine ground. After this, you need to start the engine and connect the positive contact of the device to terminal A of the sensor, also following the markings. The voltage is measured, which should be within 5 V. If the device readings are different (less than 5 V), this indicates a malfunction of the power circuit or the unit itself electronic control engine.

If during the test all the instrument readings were normal, then there is nothing to worry about. Otherwise, the TPS needs urgent replacement.

Replacement

If the check shows that the TPS is faulty, then it needs to be replaced. You don’t need many tools for this, all you need is skillful hands and a Phillips screwdriver.

The sensor should be replaced by turning off the engine and disconnecting the minus from the battery. Then you need to disconnect the sensor connector, which has a lock. Then unscrew the two screws that secure the sensor to throttle assembly. After this manipulation, the sensor is easily removed from the throttle valve axis.

Video - replacing the throttle position sensor on a VAZ2110, 2114, 2115:

Installation of a new device should be done in reverse order. In this case, you need to make sure that the throttle valve itself is closed. Usually, when a new TPS is purchased, it includes sealing ring. It is installed between the sensor and the throttle pipe. Remember to remove the old ring before installing the new sensor.

Once in place, tighten it with the machine screws until the O-ring is completely compressed. Now all that remains is to connect the connector and secure it with the latch.

After this, disconnect for 5 minutes. This is done to reset the old sensor parameters in the ECU, which in most cases are retained.

Adjustment

In some cases, it becomes necessary to adjust the throttle position sensor. This procedure may be an alternative to replacing it. And it should be carried out when obvious signs malfunctions. They were mentioned above.

Video - adjusting the throttle position sensor on a VW Passat:

To adjust, you will also need a multimeter with wires. You shouldn’t do everything by eye, as the electronic control unit will receive incorrect data. Accordingly, it will dose incorrectly air-fuel mixture with all the ensuing troubles.

Before adjustment, the sensor mounting holes need to be slightly widened. This is done so that the sensor can be rotated around its axis.

An important point: before each time removing the TPS or disconnecting its connector, you must turn off the ignition, and before each measurement, turn it on.

The sensor connector can be removed, or you can expose a small section of the connector wires hidden under the casing. Only these two wires are of interest, usually blue (plus) and black (ground). They will be needed to measure voltage during the adjustment process. If the connector is removed, then you need to connect the multimeter wires to the corresponding contacts on the sensor.

Having connected the wires to the contacts of the sensor (they should be well secured), install it in place. Do not tighten the fastening screws completely: so that the sensor does not dangle, but can be rotated. Now you need to carefully rotate the sensor counterclockwise or clockwise until the following readings are established on the device: 0.55-0.56 V. If necessary, the mounting holes must be widened to increase the angle of rotation.

When setting the required value, the TPS should be securely secured. After this, perform a voltage test. If necessary, insulate previously exposed sections of wires.

The throttle position sensor is designed to transmit information about the state of the bypass valve at a specific period to the vehicle engine ECU. This mechanism is a combination of a fixed and variable resistor.

In total, the maximum resistance of the device is approximately 8 ohms. The TPS device includes 3 contacts. A voltage of about 5 V is supplied to 1 and 2, contact 3 is a signal contact and is connected to a specific controller.

The PDZ sensor is mounted on the throttle body and reacts to its opening or closing. The resistance of the device also changes:

• with the throttle valve fully open, the voltage value at the signal contact will be at least 4 V;
• with a completely closed remote control - up to 0.7 V.

Any voltage changes are regulated by the controller. The volume of fuel required to create the air-fuel mixture is adjusted accordingly.

If the inductor is not operating correctly, the voltage may go beyond set limits, which often leads to disruption of the functionality of the power unit, and sometimes to complete breakdown.

It should be noted that a breakdown of the PDZ sensor is often the cause incorrect operation Checkpoint. Repair car engine and the checkpoint is a rather labor-intensive and costly undertaking. Therefore, if signs of malfunction of the throttle sensor are detected, it is recommended to check the functionality of the gearbox.

Main signs of device malfunction

Problems in operation can be identified by the following signs of a malfunction of the TPS, indicating a breakdown of this particular mechanism:

1. Regardless of the operating mode of the engine, the idle speed is not constant.
2. If you suddenly release the gas pedal, the engine stalls when you change the gearbox.
3. Motor power drops significantly.
4. When the engine is idling, the speed is not constant.
5. Fuel consumption has increased noticeably.
6. Despite the smooth depressing of the gas pedal, jerking is noticeable when accelerating.

In some situations, the Check Engine indicator light may come on, but it will not go out for some period. This signal should also not be neglected: it is imperative to check and eliminate errors in the operation of the device.

Checking the performance of the TPS

If during operation vehicle If at least one of the signs of a malfunction of the throttle position sensor has been detected, its functionality must be checked. To do this, the car owner does not require any special knowledge. It is enough to have a multimeter and know a clear sequence of actions.

The main thing to remember is that Check Engine is a light that is installed specifically to signal the driver about faulty engine. If it lights up, then you need to immediately contact a service station or fix the problem yourself.

If there are no problems, the light will light up when the engine starts and go out instantly when the diagnosis is complete. If the Check Engine light remains on, there is a problem with the system. In this case, you cannot do without an experienced specialist.

Regarding the identification of throttle valve malfunctions, the symptoms of which were identified during the operation of the car, there is a certain algorithm of actions:

1. The first thing you need to do is turn off the ignition, inspect the instrument panel, notice whether it is on or not. Check indicator lamp Engine, which signals the presence of problems. If the indicator does not light up, you need to climb under the hood and check the TPS.
2. Next, you will need a multimeter - a special device to check the operation of the throttle sensor.
3. It is necessary to determine the presence of a “minus”. In order not to discard each wire separately, it is worth piercing the necessary wires and measuring them.
4. The search for “mass” is carried out in the same way. There is no need to turn on the ignition during the mechanism check period.

The purpose of performing preliminary actions is to check the availability of power to the PDZ sensor. The voltage depends on the make of the car. For example, for some machines it may be only 5 V, while for other models it may be 12 V.

Algorithm of actions to determine TPS malfunctions, the symptoms of which were identified while the vehicle was moving:

• you need to turn on the ignition and pierce the wires of the required chain one by one using a multimeter. The device display should show a voltage reading of 0.7 V;
• the throttle valve opens manually: the voltage value must be greater than 4 V;
• The ignition is turned off, one connector is discarded. In the area between the slider terminal and the wire (which remains), a multimeter probe is connected;
• Now you need to manually scroll the sector and observe the readings of the measuring device. If there is a smooth increase in values ​​without sudden jumps, it means that the PD sensor is working normally. In the opposite situation, we can talk about damage (scuffing) of the resistor track.

These indicators influence the proper functioning electronic unit control unit (ECU), which controls the main operating processes of a car engine, the supply to the injectors fuel mixture. If inaccurate numbers are supplied to the ECU, then the control unit will make incorrect decisions.

For example, the throttle valve is fully open and electronic device indicates that it is closed. If such symptoms are present, this is an obvious malfunction of the throttle sensor and must be replaced.

Reasons for sensor failure

It is impossible to completely prevent breakdowns of units, parts, and electronic mechanisms of vehicles.

Possible reasons for failure of the TPS:

1. Loss of contact between the slider and the resistive layer. The reason is that the tip is broken, causing scoring on the substrate. The throttle sensor may continue to function (not correctly) until the resistive layer is completely erased. As a result, the core fails completely.
2. A linear increase in the voltage of the output signal is not provided due to a violation of the base deposition at the start of the slider stroke.

It is necessary to understand that not a single indicator on the instrument panel will indicate such a breakdown, and self-diagnosis of the car is not provided. The existence of a malfunction can only be assumed in the event of unstable operation of the motor in different operating modes.