What's wrong with the sound of the car throttle?

Throttle is a controllable valve to control the air entering the engine. After the gas enters the intake pipe, it will be mixed with gasoline to form a combustible mixture, which will be burned to do work. It connects the air filter and the engine block, and is called the throat of the automobile engine.

Throttle is one of the most important components in EFI automobile engine system. Its upper part is the air filter grille, and the lower part is the engine body, which is the throat of the automobile engine. Whether the acceleration of a car is flexible or not is closely related to the dirt of the throttle. Cleaning the throttle can reduce fuel consumption and make the engine more flexible and energetic. Whether the accelerator should be removed for cleaning is also the focus of discussion among car owners.

Classification of throttle valve

1. Traditional engine throttle

The traditional engine throttle control mechanism works through a cable (soft steel wire) or a pull rod. One end of this cable is connected to the accelerator pedal, and the other end is connected to the accelerator linkage plate.

2. Traditional engine throttle

The electronic throttle mainly uses the throttle position sensor to control the throttle opening according to the energy required by the engine, so as to adjust the intake air.

"Throttle valve" failure

The composition of electric throttle can be roughly divided into the following parts: throttle, electromagnetic driver, potentiometer, controller (some of which are not directly managed by ecu) and bypass valve. Its fault characteristics are divided into two categories: hard fault and soft fault. Hard fault refers to mechanical damage, and soft fault refers to dirt, imbalance, etc.

hard failure

The resistance part of potentiometer is formed by spraying a layer of carbon film on polyester substrate, which is actually a very low-level preparation process with low wear resistance. To put it bluntly, it is not as good as the potentiometer of our ordinary household appliances. The sliding contact consists of a row of opposing claws made of pure steel. Watch your paws! This is simply worse! In addition, there is no protective agent on the carbon film, and the falling toner leads to poor contact, which is inevitable.

Soft fault

People often worry about cleaning the throttle because the throttle is too low most of the time. Air flows through the throttle gap at high speed (tens to hundreds of meters per second), and the accumulated dust has more influence on the airflow than the throttle adjustment ability.

If there is too much sludge in the accelerator, it may cause poor engine acceleration and increase fuel consumption, which is a big worry for the owner. So what if the throttle is dirty? Cleaning can be solved.

Cleanliness and "throttling" frequency

First, circle the fixed metal bundle with a little oil to avoid the teeth slipping during disassembly. Remove the metal ring of the throttle hose. After the hose is removed, the left end is the position of the throttle. Remove the negative electrode of the battery, turn off the ignition switch, straighten the throttle plate, spray a small amount of "carburetor cleaner" into the throttle, and then carefully scrub it with polyester rag or high-spin "non-woven fabric". Deep in the throttle, where the hand can't reach can be carefully scrubbed with a clip.

When cleaning the throttle valve, it is not necessary to disassemble it, but the sealing part of the inlet steam must be cleaned, and the idling motor must be removed before cleaning. Borrowing and cleaning syringes has advantages and disadvantages. It is generally recommended that the maintenance station should not disassemble and clean to prevent other unnecessary waste, such as replacing the sealing ring or installing some other gaskets after disassembly, or leaking oil and gas during disassembly and assembly, which will delay the owner's time.

After cleaning, follow the disassembly procedure just now, and start the initialization of the throttle valve after installation. It needs to be initialized after cleaning the throttle, because the computer has a memory function when adjusting the throttle opening. Because there was sludge blockage before, in order to ensure the air intake, the computer will automatically adjust the throttle opening to keep the air intake in a normal state.

But there is no sludge blockage after cleaning. If the throttle valve still keeps its previous opening, the intake air will be too large. As a result, the engine will shake when starting, and the acceleration will be weak, and the engine fault light may light up. It needs initialization to be normal.

Cleaning frequency

How long the throttle will be dirty depends on the quality of the air filter, the brand and quality of the oil used, the road conditions, the temperature, the working temperature of the engine, the driving habits and many other aspects. Even for individuals, it is impossible to determine the time to clean the throttle with a fixed number of kilometers. The interval between cleaning the throttle for the first time in a new car is the longest. In the future, due to the continuous condensation of oil and gas in the crankcase ventilation pipe and intake pipe, the cleaning frequency will increase, and different weather conditions will also affect the dirty speed of the throttle.

Then why does the engine sometimes work normally without initialization after clearing the throttle?

That's because the throttle is not too dirty. After cleaning, its air inlet changed little. However, the change of throttle after cleaning is invisible to the naked eye and needs to be initialized.

In fact, initialization is very simple. You can do it with a special computer or by hand, but it is not as fast as a computer, and sometimes it will fail. It doesn't matter if you fail. Do it again. According to different cars, there are two initialization methods:

Initial method

The first is the second gear of the key, that is, the gear where the instrument indicates full light. Then wait 20 seconds, and then step on the accelerator. After holding for about 10 second, release the throttle, turn off the ignition switch, pull out the key, and the initialization is complete.

The second method is to open the second key, hold it for 30 seconds, then turn off the ignition switch and pull out the key. It should be noted that after the completion of the two methods, it will take some time before you can try to ignite. Generally, you can wait 15-20 seconds, and then ignite to see if the refueling is normal and the engine fault light is off. If you fail once, do it again until you succeed. You can usually succeed once, at most twice.

However, depending on the car, the method of restoration is different. Some cars must be initialized by a computer. If so, it is recommended that the owner send the car to a shop with professional equipment for cleaning.

I-word duration

2021165438+122 October to 2021165438+/24 October.