How to Clean the Throttle Body Yaris And New Limo?

How to Clean the Throttle Body Yaris And New Limo? – Sometimes it’s the little things that often lead to our car in big trouble. Not infrequently just because the air filter is dirty, the car engine becomes difficult to start or even shuts down suddenly when we are traveling. Not to mention involving the cooling system and lubrication system. All the little things but the big impact. Regarding the cleanliness of components, it is also an important part of an engine, one of which is the cleanliness of the throttle body.

The throttle body or the gas valve housing of the Yaris and New Limo are physically the same, there is no difference. The throttle body for the new limo and Yaris uses the ETCS-i system (Electronics Throttle Control System – Intelligence) so there is no ISC valve for Idle Control Speed. Therefore, for vehicles from Toyota that already use ETCS-i, we will not find Gas Straps or ISC Valves. For example, those who have used ETCS-i are the Toyota Yaris, New Limo, and others. For that, let’s first understand ETCS-i.

Read more: Toyota CVT Transmission Problems Due to 3 Wrong Habits

Getting to know the Throttle Body with the Electronics Throttle Control System – Intelligence

In modern vehicles, almost all – if not all – gasoline vehicles use an injection system. The gasoline injection system or Toyota technology often people call it electric fuel injection (EFI) uses an injector to spray fuel directly into the combustion chamber. Meanwhile, there is a mechanism that becomes the entrance of air into the special combustion chamber which we call the throttle body.

How does a throttle body work on a car?

Currently, all new cars use the ECU or Engine Control Unit. This system utilizes various sensors that work to control the vehicle engine. One of them is the throttle position sensor which is part of the throttle body component. Its position is fused to the throttle body associated with the gas valve.

What is the function of the throttle position sensor and how does it work, see in the following discussion.

Definition and Functions of the Throttle Position Sensor

The throttle position sensor serves to regulate and balance the fuel on the vehicle engine. The position itself becomes one with the throttle body which is connected directly to the valve. The reason for placing this sensor component is to ensure that the air intake valve has the appropriate opening angle. When a change in valve shift appears, the sensor will work to send a signal to the ECU device.

The signal sent is then processed so that there is a supply or injection of fuel into the combustion chamber. In addition to working to send signals, there are still throttle position sensor functions as follows;

Clean the Throttle Body Yaris
TPS Sensor and its terminals – Clean the Throttle Body Yaris.
1. Information on Mode and Vehicle Conditions

This first function is to provide information about the mode and condition of the vehicle. TPS will know the position and condition of the engine with changes in the condition of the throttle valve. Whether it’s when the air intake valve is fully open, or half to fully closed. This condition will indicate a difference in acceleration, for example, when the valve is fully open, the acceleration increases.

Meanwhile, when the valve is fully closed the engine will die. When the valve is half open, the engine is at medium speed.

2. Corrector for Air and Fuel Comparison

In the second function, TPS will provide a correction in the form of the ratio of the fuel and air mixture. The information obtained by TPS will be used to correct the air and fuel mixture.

For example, when the air intake valve is fully open, the engine also requires a lot of fuel. The opposite also happens, namely, when the valve is open slightly, the salt only needs a little fuel. The goal is that the amount of air and fuel that enters is balanced. That way the combustion that takes place can create perfect power.

3. Provides Control on Fuel Cut

Not only correcting, but TPS also works to control fuel cuts. In its work, TPS will get information based on that data, and TPS can later control the work of the injectors.

So when the gas valve is open and the sensor gives such a signal, the injector will light up for a longer time. Likewise, when the sensor states that the gas valve is slightly open, the injector lights up briefly.

4. Stopping AC Switches and Emission Control

The last function is to turn off or stop the AC switch and emission control. Information obtained by TPS will later be used to stop or control exhaust emissions.

Read more: Causes of AC Not Cold when the Car is Stopped

For example, when the load is excessive so that the power works more optimally, the AC switch will turn off automatically. The effect is that the engine performance is maintained.

How the Throttle Position Sensor Works According to Type

There are several types of TPS that manufacturers currently use on their cars. Each has different specifications. Thus, the workings of this TPS component also vary based on the type. In order not to misunderstand TPS, you can listen to the following types and how they work.

Clean the Throttle Body Yaris

1. Variable Resistor Type

The first type utilizes a resistor as a modifier of the size of the sensor output voltage signal. There are three types of terminals used, namely input voltage or VC, output terminal, and mass terminal.

The voltage on the sensor comes from the ECU which is 5 voltage. The following is an explanation of each terminal.

  • The VC terminal, also known as the current terminal, will send a 5-volt reference voltage to the sensor.
  • VTA1 terminal, which is the terminal that is the output of the sensor with live electricity. The magnitude of the voltage will be the information that shows the angle of opening of the valve.
  • Terminal E2, is the base terminal and we usually call it mass and go to the base ECU. The goal is that the process runs smoothly, the cable itself is black.

This type of TPS has an inverse ratio between the gas throttle opening and its resistance. The way it works itself is that when idle, the voltage released by the TPS sensor is 0.6 to 0.9 volts. Unlike the throttle valve which is fully open, because the voltage is 3.5 to 4.7 volts.

2. Point Contact Type TPS Sensor

There are two types of IDL and PSW signals that exist in this type. The IDL type is used to stop the fuel flow and the PSW signal is used to inject fuel. Meanwhile, the point contact type function is to detect changes and the intake air valve throttle opening and the terminal type for this type of TPS sensor is point contact. The same thing happens to the type of variable resistor that utilizes three wires.

Sensor detection can only be done when the throttle valve is in the 0 to 5-degree position, namely in the idle position. At the same time, the position of the IDL terminal with the E1 terminal will be connected. Meanwhile, when the throttle valve is between 6 and 49 degrees, the point contact sensor will not be connected. That’s why the ECU will detect it as an intermediate spin.

When the throttle valve opens from 50 degrees to fully open, the terminal on the connected TPS sensor is the PSW terminal. In that position the ECU will detect the TPS is at high speed.

3. Induction Type TPS Sensor

This third type is the throttle position sensor or TPS which utilizes the sensor in the induction position. This type of TPS sensor uses an IC element to detect the angular position of the air intake valve.

Derived from this information later the system will convert the dc signal to ac to produce a magnetic field. This magnetic field will induce the pickup coil. So that the voltage result is a signal to the ECU to determine the throttle valve position.

4. Hall Effect Type

In this fourth type, the way it works is by utilizing the hall effect, which is a component to produce a voltage that varies and becomes a magnetic response. When the input voltage is applied to the hall effect, the output voltage will be adjusted from the throttle valve position.

Electronics Throttle Control System – Intelligence

Clean the Throttle Body Yaris
Electronics Throttle Control System – Intelligence (ETCS-i) and sensors – Clean the Throttle Body Yaris.

Electronic throttle is an automobile technology that electronically “connects” the accelerator pedal to the throttle to replace the mechanical link. The system of the electronic throttle consists of three main components, namely as follows;

  • Air intake valve spring modules generally have two or more independent sensors. The system will connect these sensors with the car’s wheel drive system.
  • Normally, the electric motor will open and close the throttle valve (sometimes people also refer to it as an electric or electronic throttle body aka ETB).
  • Power train control module for the engine ( PCM or ECM ).

Read more: ECM vs PCM vs ECU what are the differences?

The following is how the electronic throttle works. This Electronic Throttle allows a separate accelerator pedal with a direct intake air valve. Well, buddy, how the electronic throttle works is through the electronic system first. The goal is to adjust the electronic throttle to the needs of the engine. The ECU will calculate all these values based on input from several related sensors. Thus, it will create a system efficiency that is in the components in the electronic throttle system. In addition, this electronic throttle also works by being a bridge between the gas pedal and the electronic throttle.

Therefore, the system or the workings of the electronic throttle is a setting whose results are in digital form. So that it can function optimally on your vehicle.

How to Clean the Throttle Body Yaris And New Limo?

Cleaning the throttle body with the ETCS-i system is easier than other types of throttle bodies. This is because we only need to clean the area around the throttle valve. We don’t need to clean the ISC like cleaning the TB of injection cars that use ISC.

Back in accordance with the title of the article about cleaning the Toyota Yaris Throttle body, how to clean it is quite easy and simple. But we need to prepare some equipment as follows.

  1. Carburetor or Injector Cleaner.
  2. Open wrench sizes 10 mm or screwdriver plus and screwdriver minus.
Clean the Throttle Body Yaris
The position of the Toyota Yaris throttle body in the engine room – Clean the Throttle Body Yaris.

While paying attention to the picture above, please do the following steps.

  1. Loosen the air duct fixing bolt see number 1.
  2. Open the VSV hose leading to the intake chamber in picture no 2.
  3. Loosen the air duct fixing bolt see no 3.
  4. Open the MAF (Mass Air Flow) socket and see no. 4.
  5. Open the two buttons of the air filter number 5 and number 6 next to it.

After opening all the sections shown above will look like the image below.

Air filter Toyota Yaris

After we open it like the picture above, around the air intake valve, we will see dirt in the form of dust that sticks. The dust will get thicker if we rarely clean or replace the air filter.

Dust that sticks to the side of the throttle valve will affect the engine speed at idle, which can cause the engine rpm to be higher or lower. Generally, the engine rpm will be lower because of the amount of dust. At other times if the dust gets on the gas valve or blocks the throttle valve it will make the rpm at idle higher.

The next step is to clean the throttle body using a carburetor cleaner or injector cleaner. This we do without lowering or without disassembling the throttle body from the intake chamber.

How to clean the throttle body

How to clean the throttle body

Ask one person for help to turn the ignition on and press the accelerator pedal. The goal is to open the throttle valve so that it is more optimal when cleaning. Then clean it with a spray cleaner as shown in the picture above. Once it’s clean enough and doesn’t need to be too much or too much cleaner.

The next step is to start the engine once or twice to suck and remove the remaining cleaner residue that is in the throttle body. The engine will not start easily. Why? This is because we have not installed Mass Air Flow or MAF. This also results in the check engine light coming on when the engine is running. However, there is no need to worry because we can reset it by removing the negative terminal of the battery for a while. We do all these activities before reassembling the parts that we have dismantled.

Read more: 2 Ways to Manually Reset ECU when Check Engine is On

Maybe you will ask why we don’t first install all the parts of the machine as a whole. And then after that, start the engine until it comes to life at once to burn the rest of the cleaner. Too much cleaner residue on the throttle body when starting the engine. This will make the engine unable to start because the air-fuel mixture is too fat or fails to start which will sometimes also trigger the check engine light to come on. If this happens we have to reset the ECU to turn off the Check Engine light by removing the Negative Battery terminal.

For a new limo, after removing the battery terminal or after resetting the ECU, usually the first time the engine starts will make the idle rpm too low. We can overcome this by holding the gas pedal or idling at around 1000 rpm for about 10 to 12 minutes. After that, the machine will return to normal.

After understanding the description above, reassemble the parts that we disassembled earlier. Anything? Namely the air duct that connects the throttle body with the air filter, attach the VSV hose, install the air filter cap and finally install the MAF Sensor socket.


If we first install the mass air flow sensor in the air filter cover (air cleaner) before starting or when cleaning the throttle without opening the MAF Sensor and then the engine starts and the engine starts successfully and the check engine light does not turn on after the engine starts, usually the engine rpm will up to 1500 or 2000 rpm at idle. We can solve this problem by removing the negative battery terminal for a few seconds (30 seconds) to reset the ECU and the rpm is back to normal.

So in conclusion, if after cleaning the throttle body the engine rpm goes up for the ETCS-i system, the way to lower the engine rpm is to reset the ECU.

1 thought on “How to Clean the Throttle Body Yaris And New Limo?

  1. Pingback: 5 Easy Steps to Clean the IACV (Idle Air Control Valve)

Leave a Reply

Your email address will not be published. Required fields are marked *