If the engine idling speed is unstable or it stalls after a sharp closing of the throttle, it may need a throttle flush. We tell you why a dirty throttle may be to blame, what this unit affects and, most importantly, how to clean the throttle so that everything works as it should.
What is a throttle plate
Throttle valve (or simply throttle) – a device that regulates the amount of air that is used to create a fuel-air mixture. By depressing the accelerator pedal, the driver, through an actuator system (mechanical or electronic), opens the throttle and thereby increases the flow of air drawn or blown into the engine cylinders.
In older cars (up to about 2003), the throttle was directly connected to the accelerator pedal by a linkage or cable. In modern cars, the throttle is controlled by the engine ECU, and the right pedal has become “electronic”, with a position sensor that transmits a signal to the ECU via wires. When the choke is fully closed, air flows into the cylinders through the idle speed regulator (RCH) – exactly enough to keep the engine running at idle speed. Opening the choke increases the intake capacity. More air (and therefore more fuel) enters the engine cylinders, and the engine speed and thrust increase.
Correct operation of the choke directly affects engine efficiency. If the flap is dirty and opens, and most importantly, closes, not completely, then the motor fails, there are “dips” during acceleration, fuel consumption increases. To avoid such unpleasant situations, you should clean the throttle valve as necessary.
Where is the throttle valve
In different car models, the throttle valve can be located in different places, taking into account the engine layout and other features of a particular car. You should look for the choke between the air filter and the inlet of the intake manifold. Usually, it has its own housing with integrated in it RCH, actuator (in case of “electronic” gas pedal) or drive cable. In sporty engines there are individual throttles for each cylinder, but it is exotic.
In mass in-line engines, the throttle unit is most often “in plain sight”, and access to it is free. It is easy to get to it yourself if you have skills and tools. But in V-shaped and opposition engines, access to the throttle can be difficult. In such cases, it is easier to go to the service for cleaning, combining it with other maintenance operations.
Why to clean the throttle
Is it worth cleaning the throttle? It would seem that only air passes through it. However, in fact, in a modern engine, in addition to air from the atmosphere (which is also not perfectly clean, despite the filter), part of the exhaust enters the intake (through the recirculation system), and the crankcase gas ventilation system is connected to the intake manifold.
As a result, the flap and the throttle itself are covered with soot, oil, fuel components, especially if the gasoline used is not of the highest quality. This leads to engine malfunctions, reduction of its power and increased fuel consumption.
All because deposits on the internal surfaces of the throttle prevent the normal movement of the flap. That is, it will not be able to fully open or close, and can also stick.
How often to clean the throttle linkage
The ideal solution would be to flush the throttle every 30-50 thousand kilometers. However, this interval is actually very individual. For example, in large cities, the air is usually relatively clean and the gasoline is of good quality. In such conditions, the throttle unit can serve without problems and 100 thousand kilometers. But when operating on dusty dirt roads and using low-quality fuel, deposits accumulate much faster. Then you will need flushing of the choke.
How to understand that the throttle plate needs cleaning
Throttle valve cleaning should be a preventive measure, but sometimes it is necessary to perform it already after the fact of problems with the engine. Several signs can indicate the need to clean the throttle:
The first symptom that requires attention is unstable engine operation at idle speed. If you notice that the engine speed begins to “jump”, it may indicate a poor condition of the choke and its incorrect operation. For example, it may not close properly. In addition, dirt can partially clog the idle speed channels.
The second sign is a change in the dynamics of the car. If your car became slower and with failures to respond to the accelerator pedal, it can also be associated with a large amount of deposits on the throttle. When the choke becomes clogged, it begins to stick and turn sharply on its axis. If you feel that your car is not responding as crisply to the gas, then the throttle plate probably needs to be cleaned.
The third symptom is an increase in fuel consumption. Sometimes quite substantial, up to 30%. Again, the reason is the lack of air, and this leads to a change in the optimal composition of the fuel mixture, its inefficient combustion and, accordingly, higher fuel consumption.
Is it possible to clean the throttle at home? Yes, but there are nuances.
How to properly clean the throttle valve
First, we note that in modern cars after washing the throttle may need its adaptation. During this procedure, data on the extreme positions of the choke are written into the memory of the ECU. So, if after cleaning you have problems (for example, the idle speed will increase sharply), you will have to visit the service.
How to flush the throttle valve, if you still decide to act on your own? Adhere to the following algorithm:
- First disconnect the battery. This is necessary for safety, so that when disassembling the assembly not to damage the electronics of the throttle valve or damper sensor as a result of an accidental short circuit.
- The next step is to disconnect the throttle assembly from its mounting location. It is usually secured with several bolts or screws and connected to the air cleaner and/or intake manifold by ducts. After unscrewing all the fasteners, carefully remove the choke from the intake system.
- Now you can start cleaning the throttle plate. First, very carefully remove the accumulated loose dirt with a clean rag or brush. Then you can apply a special cleaner designed for cleaning the throttle. Apply it to a rag and gently wipe the surface of the choke. Do this carefully so as not to damage the electronics or bend the damper itself.
- After you have cleaned the damper, allow it to dry. Then reinstall it and reattach the assembly in the reverse order. Don’t forget to connect the battery and test the engine operation.
What to clean the throttle plate at home
The most popular means – special cleaners, which can be purchased in auto stores. They contain chemicals that help dissolve and remove accumulated deposits. To use it is enough to spray the cleaner on the flap and keep it for some time. Then you should rinse the choke with water. After rinsing the throttle plate, it is wiped dry (it will also be useful to blow it with compressed air) and put it back in place.
How to clean the throttle, if there are no auto stores with chemicals nearby? You can use isopropyl alcohol: pour it into a container and put the removed assembly there. Alcohol should be of high concentration to ensure effective cleaning. Then the flap should be gently wiped with a soft brush or cloth to remove accumulated deposits. Next, rinse with water and after drying, install it back on the vehicle.
The most effective cleaning of the throttle is in an ultrasonic bath. This is a special device that creates vibrations of high frequency to destroy and remove deposits from the flap. For this procedure, the choke must be removed and placed in an ultrasonic bath filled with a special cleaning solution. The time required for cleaning is not regulated and depends on the degree of contamination. Next, the flap should be rinsed with water, let it dry and install it back on the car.
Totals
- The throttle valve doses the air supply to the cylinders and thus controls the revs and thrust. It is one of the most important elements of the engine’s power system.
- The choke is located in the area of the intake manifold and, as a rule, is “in plain sight.”
- Clean the throttle better every 20-30 thousand kilometers.
- O problems with the throttle can usually be guessed by changes in idle speed, unstable engine performance, a drop in traction and increased fuel consumption.
- Throttle unit can be washed by yourself if you have the necessary skills and special chemistry, which is sold in auto stores.