What Causes Abnormal Noise in BMW's Acceleration Engine?

What is the content of Driving Test Subject 4?

According to the "Regulations on the Application and Use of Motor Vehicle Driving Licenses", the content of Subject 4 is safety and civilized driving knowledge questions, consisting of 50 questions, mainly in the form of cases, pictures, animations, etc., with a full score of 100 and a passing score of 90. Subject 4, also known as the Subject 4 theory test or driver theory test, is part of the motor vehicle driving license assessment. After the implementation of the Ministry of Public Security Order No. 123, Subject 3 was divided into two parts: in addition to the road test, a safety and civilized knowledge test was added, commonly known as Subject 4. It is not a separate subject, but because this test is conducted after Subject 3, it is commonly referred to as the Subject 4 test. Officially, there is no Subject 4. The safety and civilized driving knowledge test is conducted after Subject 3. There is no limit to the number of attempts for Subject 4. If the first test on the day is not passed, an on-site retake is allowed once. If it is still not passed, a new appointment is required, and no retake fee is charged. However, it should be noted that the validity period of the driving skill test permit is three years. If the applicant does not complete the test within the validity period, the results of the already passed subjects will be invalidated. Subject 4 test notes: Test time: The test time is 45 minutes, and if 12 points (6 questions) are wrong during the answering process, the test will be terminated. Number of questions: According to the type of driver's license being tested, 50 questions are selected proportionally from the corresponding Subject 4 question bank, with each question worth 2 points. Test question types: The test questions are divided into single-choice questions (including true/false questions) and multiple-choice questions. The first 45 questions are single-choice, and the last 5 are multiple-choice. The test questions include animation questions, picture questions, scenario identification questions, and text narrative questions. Retake notes: If Subject 4 is not passed, only Subject 4 needs to be retaken. The driving school will schedule the retake, and there is no limit to the number of retakes. No retake fee is required for Subject 4 retakes. Subject 4 test tips: Strengthen the error-prone areas and find the reasons for mistakes. For marked questions, do not just look at the correct answer and memorize it. Refer to regulations, textbooks, or reference books to find out the reason for the mistake and understand and digest the reason. Classify and summarize the test questions. Refer to the question bank analysis for classification and find similar questions: There are many similar questions in the question bank that are easy to confuse, so they need to be taken out for summary and analysis. For example, the patterns of walking, hiking, pedestrian crossing, and pedestrian crossing signs in traffic signs are very similar and easy to confuse. During study, they should be classified so that mistakes are less likely to occur. Find memory techniques: There are many questions with numbers in the question bank. The numbers can be summarized for easier memory. There are a total of 3 subjects in the driving test: Subject 1, Subject 2, and Subject 3. Subject 3 is divided into two parts. Subject 1 refers to the test subject of road traffic safety laws, regulations, and related knowledge; Subject 2 refers to the test subject of site driving skills; Subject 3 refers to the test subject of road driving skills and safety and civilized driving knowledge.

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Why Does the Radiator Make Loud Noises?

The radiator may produce noise, which could be related to the fan belt or the balance of the fan blades. It might also be due to the radiator being dirty, leading to poor heat dissipation, reduced airflow, increased fan speed, and consequently, louder wind noise. This issue does not affect normal usage. It is recommended to clean the radiator and fan blades, and check if the fan mounting screws are loose. If the problem persists, consider replacing the car radiator fan. The car radiator consists of three parts: the inlet chamber, the outlet chamber, and the radiator core. The coolant flows inside the radiator core, while air passes outside the radiator. The hot coolant cools down by dissipating heat to the air, and the cold air heats up by absorbing the heat from the coolant. Usage and maintenance methods are as follows: 1. The radiator should not come into contact with any acid, alkali, or other corrosive substances. 2. It is recommended to use soft water. Hard water should be softened before use to prevent internal clogging and scale formation in the radiator. 3. To prevent corrosion of the radiator, always use coolant produced by reputable manufacturers and compliant with national standards for long-term anti-rust performance. 4. During the installation process, avoid damaging the cooling fins or bumping the radiator to ensure proper heat dissipation and sealing. 5. When refilling the radiator after completely draining it, first open the engine block's drain switch. Once water starts flowing, close it to prevent air pockets. 6. Regularly check the water level during normal use, and add water only after the engine has cooled down. When adding water, gently open the radiator cap and keep your body as far away as possible from the filler neck to avoid burns from high-pressure steam. 7. In winter, to prevent the core from cracking due to freezing, drain all water from the radiator by opening the radiator cap and drain switch if the vehicle is parked for an extended or intermittent period. 8. The storage environment for spare radiators should be kept ventilated and dry. 9. Depending on actual conditions, users should thoroughly clean the radiator core every 1 to 3 months. When cleaning, rinse with water against the direction of the incoming airflow. 10. The water level gauge should be cleaned every three months or as needed. Disassemble all parts and clean them with warm water and non-corrosive detergent.

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How to Escape If a Car Falls into Water?

When a car falls into water, it does not sink immediately. You can use the one and a half to even two minutes before sinking to escape through the doors or windows. Even if the car submerges to the bottom, there are methods to escape because it may take about half an hour for the cabin to fill with water. The exact time depends on whether the windows are open, the car's sealing, and the depth of the water. The deeper the car sinks, the greater the water pressure, and the faster the cabin fills. Here are the steps to handle a car falling into water: 1. Once submerged, do not panic. Hold onto the handrail or the back of the seat tightly, lean back against the seat, and roll with the car as it turns. This prevents passengers from being knocked unconscious before the car rolls into the water, which could lead to drowning due to inability to self-rescue. 2. During the fall, keep your lips closed and teeth clenched to avoid biting your tongue. Cars have some watertight capabilities, so after entering the water, do not rush to open the windows or doors. Instead, close all doors and windows to prevent water from rushing in. The end with the engine will sink first, while the other end's roof will trap a pocket of air, which can be used to survive. If time permits, turn on the headlights and interior lights to see your surroundings and aid rescuers in locating you. Unfasten your seatbelt. Stick your head into the air pocket to breathe. If the engine is in the front, climb to the back seat. Use the time to close windows and ventilation ducts to preserve air inside the cabin. 3. As the car gradually sinks, water will enter through gaps until the pressure inside and outside equalizes, at which point the water level inside the cabin will stop rising. Stay calm and wait patiently during this time. Trying to force open the door when the pressures are unequal will only cause chaos and reduce your chances of escape. 4. Once the water level stops rising, take a deep breath, then open the door or window and jump out. Remove your outer clothing first. If the door cannot be opened, use a car repair tool or wrap clothes around your hand to break the window glass. Exhale slowly as you rise. The air pressure in the car and your lungs matches the water pressure. As you rise, the air in your lungs will expand, and failing to exhale excess air can damage your lungs. 5. If there is more than one person in the car, hold hands and escape together, ensuring no one is left behind.

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What is the purpose of automotive urea?

Automotive urea serves the function of treating exhaust gases to reduce pollutants in the emissions. It is a liquid used in SCR (Selective Catalytic Reduction) technology to decrease nitrogen oxide pollution in diesel vehicle exhaust. Its composition consists of 32.5% high-purity urea and 67.5% deionized water. The operation process of the SCR system is as follows: when nitrogen oxides are detected in the exhaust pipe, the urea tank automatically sprays diesel exhaust fluid (DEF). The DEF and nitrogen oxides undergo a redox reaction in the SCR catalytic converter, producing harmless nitrogen gas and water vapor that are then emitted.

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What Car Insurance Should You Buy?

Car insurance that should be purchased includes: 1. Compulsory Traffic Insurance: This is a mandatory insurance required by the state, and all vehicles must purchase it; 2. Third-Party Commercial Liability Insurance: Since the compensation amount of compulsory traffic insurance is limited, purchasing third-party insurance can cover the excess amount that compulsory traffic insurance does not cover; 3. No-Deductible Insurance: When compensation is required for an accident, the insurance company normally covers 80% of the loss; 4. Vehicle Damage Insurance: Vehicle damage insurance is a necessary coverage. Whether the car suffers from collisions, scratches, water damage, etc., it can be compensated by the insurance company.

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Why do newly replaced brake pads not brake effectively?

Newly replaced brake pads may not brake effectively because their surfaces are not perfectly flat. During braking, small protrusions on the surface will contact the brake disc first, resulting in reduced contact area and lower friction force. This condition will improve after a break-in period. Brake pads are crucial components in the braking system and are also wear-prone parts. It's normal to experience reduced braking force immediately after replacing brake pads. Automotive brake pads, also known as brake linings, refer to the friction materials fixed on the rotating brake drums or discs. The friction linings and blocks bear external pressure to generate friction, thereby achieving the purpose of vehicle deceleration.

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What Causes Abnormal Noise in BMW's Acceleration Engine?

What is the content of Driving Test Subject 4?

Why Does the Radiator Make Loud Noises?

How to Escape If a Car Falls into Water?

What is the purpose of automotive urea?

What Car Insurance Should You Buy?

Why do newly replaced brake pads not brake effectively?

Does Revving in Neutral Gear Damage the Car?

How to Clean a Dirty Car Roof?

What Are the Reasons Why the Car Window Glass Cannot Be Rolled Down?

Can a Car Bought on Loan Be Sold?