What to Say to the Examiner When Getting in the Car for Subject 3?

Is Engine Oil Leakage a Major or Minor Issue?

Engine oil leakage is not a major problem, but it is harmful. The following are the hazards of oil leakage and an introduction to engine maintenance: Hazards of engine oil leakage: Engine oil leakage is harmful, with the main hazard being the loss of oil, which leads to waste, insufficient oil levels, and engine damage. The damage is not caused by the leakage itself but by the insufficient oil pressure resulting from the leakage. Therefore, it is essential to closely monitor the oil level. Some vehicle models have oil level displays, which prevent the oil level from unknowingly dropping below the normal range. Engine maintenance: The three filters and oil in a car need to be replaced. In the routine maintenance of vehicles with gasoline engines, the most frequently replaced items are the three filters and the engine oil. The three filters refer to the gasoline filter, air filter, and oil filter. These filters prevent impurities from entering the engine, which could cause abnormal wear or operation of the engine.

14

3

Share

What does T-Box failure mean?

T-Box failure refers to problems with the vehicle's T-BOX in the telematics system, requiring a visit to the 4S shop to check the fault code, which will then determine the fault information. Most issues typically occur with the radar probe, making it impossible to obtain vehicle information. Here are some related details: 1. Structure of the T-Box: The T-Box structure includes an STM32F103CBT6 main controller and a dual-core STM32F105RBT6 processor. In addition, GPRS, GPS, a six-axis G-Sensor, and a vibration sensor are called upon by the main controller, along with two 12V outputs. The vehicle's T-BOX communicates with the host via CAN bus, enabling the transmission of commands and information, including vehicle status data and control commands. 2. Function of the T-Box: The T-Box has a variety of functions, the most common being remote query, remote control, and security services.

11

3

Share

Does Unmanned Car Washing Damage Car Paint?

Currently, unmanned car washing does not cause damage to car paint. Common vehicle scratches and their causes: Spiral marks, accurately referred to as sun swirls, are fine spiral-like patterns visible under sunlight, while rainbow-like patterns are known as glare marks. Using unclean cloths to vigorously wipe the car can also leave such marks. Sand is the main culprit behind scratches. Whether washing manually with a cloth or using an automatic car wash machine, directly wiping the car body with a cloth can trap dirt in the fabric, leading to scratches when rubbed against the surface. Safety of brushes in automatic car wash machines: The brushes in automatic car wash machines are made of soft foam material. Taking a certain automatic car wash machine as an example, it uses imported EVA foam brushes with very low material density, capable of filtering fine particles above PM2.0. The brush ends are forked with an inverted trapezoid structure, soft and smooth, preventing sand from being trapped and ensuring no harm to the car paint. Safe cleaning methods: After pre-washing, the brushes are activated. During the washing process, the program monitors the safe current value to ensure the brush's pressure on the car body, preventing high-friction surface contact. Due to the centrifugal force from rotation, sand cannot adhere to the brush surface. Under the influence of inertial centrifugal force, sand is flung away from the brush surface in the opposite direction of the car body. High-pressure water nozzles continuously spray water onto the brushes, thoroughly cleaning them with each rotation, making it impossible for sand and dirt to damage the car body. Effective drying methods: Water droplets left after washing can easily form convex lenses, reflecting sunlight and causing localized high temperatures that may burn the car paint or leave watermarks. Therefore, a certain automatic car wash machine is equipped with an intelligent drying mode. After cleaning, the profile lifting top wind and fixed side wind drying system automatically adjusts the wind curtain direction, speed, and pressure based on model parameters obtained from the cleaning brush pressure sensor system, ensuring the high-intensity, high-airflow super wind curtain achieves optimal drying. Safety of car wash liquids: Some alkaline car wash solutions, such as dish soap or even 84 disinfectant, may clean the car effectively at the time but can accumulate over time, corroding the painted surface and leading to dullness or cracks. The neutral imported car wash liquid used can effectively prevent car paint from being damaged by excessive acid or alkali during washing. Shining water wax: After the weak water wash is completed, the automatic car wash machine automatically sprays shining water wax, which repels water, enhances the car's surface brightness, and provides short-term (3-5 days) protection for the car paint. Not only does it not damage the car paint, but maintenance is also something the automatic car wash machine quietly performs.

17

3

Share

How Long Does Gasoline Last in the Fuel Tank?

Gasoline can typically last for about 3 months when stored in a sealed fuel tank at room temperature. Here are some relevant details: 1. The effective components of gasoline are its light fractions, which are highly volatile. Over time, the combustible portion of stored gasoline decreases, while the concentration of heavy gum-like substances increases. Using such gasoline not only reduces engine performance but can also lead to clogged fuel injectors and rapid carbon buildup in the engine. 2. The shelf life of gasoline is primarily determined by its oxidation stability, which refers to how easily the gasoline's quality changes during storage, distribution, and use. If the gasoline shows minimal changes, it indicates good stability and a longer storage period.

7

3

Share

What Problems Can Occur When Adding Sugar to an Engine?

Sugar is insoluble in oil. If sugar is added to an engine, it will not dissolve under normal conditions. As the engine operates and generates continuous high temperatures, the sugar gradually melts and turns into a sticky substance, causing the engine oil to become extremely viscous. This prevents normal circulation and effective engine cooling. As the oil pipes and oil pump become clogged, the engine may gradually exhibit symptoms such as loss of power, increased noise, sudden stalling, and failure to start. If adding sugar to the engine results in symptoms like loss of power, increased noise, or failure to start, a major engine overhaul will be required. However, a major engine overhaul is a highly complex process. Components such as clogged oil pipes and the oil pump need to be completely replaced, and the oil pipes must be thoroughly inspected and cleaned. Moreover, the damage caused by adding sugar to the engine is considered intentional sabotage. Therefore, neither insurance nor the warranty from the 4S shop will cover the repairs, meaning the vehicle owner will be responsible for all repair costs. Even after repairs, the car's safety and performance may not be fully guaranteed.

19

2

Share

What Causes Severe Body Vibration When Accelerating?

Here are the possible reasons for severe body vibration when accelerating: 1. Damaged spark plugs. 2. Worn spark plug electrode gap leading to insufficient spark. 3. Incomplete combustion of the air-fuel mixture causing vibration during acceleration. 4. Cracks in the ceramic part of the spark plug resulting in no spark, causing one cylinder to misfire which also leads to acceleration vibration. 5. Poor quality gasoline leading to inadequate fuel injector atomization, causing incomplete combustion in the cylinder and resulting in idle vibration. It is recommended to use higher octane gasoline after finishing the current tank and perform a fuel system cleaning.

7

2

Share

What to Say to the Examiner When Getting in the Car for Subject 3?

Is Engine Oil Leakage a Major or Minor Issue?

What does T-Box failure mean?

Does Unmanned Car Washing Damage Car Paint?

How Long Does Gasoline Last in the Fuel Tank?

What Problems Can Occur When Adding Sugar to an Engine?

What Causes Severe Body Vibration When Accelerating?

What Causes the Engine to Buzz When Accelerating?

What causes the whistling sound during engine idle?

Where does the outside air enter in a car's external circulation system?

What is a Jeep?