What items are required for Subject 4?

Why does the 10th-generation Civic's AC only blow air without cooling?

The reasons why the 10th-generation Civic's AC only blows air without cooling are as follows: 1. Refrigerant quality and purity: The quality and purity of refrigerant play a crucial role in vehicle AC systems. Typically, inferior refrigerant leads to inefficient AC operation. 2. Condenser and radiator: The heat dissipation condition of the condenser and radiator also affects AC performance. Long-term accumulation of debris and dust can cover these components if not cleaned regularly. 3. Refrigerant quantity: The misconception that more refrigerant is better is incorrect. During refrigerant charging, the amount must be precisely controlled - insufficient quantity causes low pressure in AC lines, while excessive quantity creates overpressure. 4. Expansion valve quality: As a key component in the refrigeration system (usually installed between the receiver-drier and evaporator), inferior expansion valves prevent the refrigerant from functioning properly.

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Should private cars use water-based or dry powder fire extinguishers?

Both have their own characteristics and are suitable for vehicle use. You can choose according to your specific needs. Below is a detailed introduction to dry powder and water-based fire extinguishers: 1. Dry powder fire extinguisher: It relies on the chemical inhibition reaction of volatile decomposition products of inorganic salts in the dry powder to extinguish fires, or the dry powder particles fall on the surface of combustible materials to isolate oxygen and extinguish the fire. Dry powder fire extinguishers are fast and effective, inexpensive, cost-effective, and widely applicable, but they produce a lot of dust and are somewhat difficult to operate. 2. Water-based fire extinguisher: It sprays fire-extinguishing agents to evaporate heat from the fire scene, rapidly reducing the temperature of the fire scene and inhibiting thermal radiation. Surfactants quickly form a water film on the surface of combustible materials, isolating oxygen and providing both cooling and isolation effects while participating in fire extinguishing, thus achieving rapid fire extinguishing. Water-based fire extinguishers are dust-free, anti-suffocation, have good fire extinguishing effects, and are non-toxic and environmentally friendly, but they are more expensive.

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Where is the engine number stamped on the Wuling Zhiguang?

The engine number of the Wuling Zhiguang is located on the left side of the engine cylinder block. It usually consists of a combination of 7 to 8 digits and letters. In addition to the above method, the engine number can also be checked through the following 4 ways: The vehicle's driving license prints the engine number, usually located on the second last line; The motor vehicle registration certificate will indicate the engine number; The car purchase invoice will indicate the engine number; The vehicle purchase tax payment certificate will indicate the engine number. It should be noted that the engine number is not the same as the engine model. The engine model refers to the specifications and size of the engine within the manufacturer, and engine models can be the same. The engine number refers to the production number of the engine, each engine can only use one engine number and each engine's number is unique.

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What is the fuel tank capacity of the Changan Yuexiang V3?

The fuel tank capacity of the Yuexiang V3 is approximately 36 liters. Below is a related introduction to the Changan Yuexiang V3: 1. Power: The Changan Yuexiang V3 is equipped with Changan Automobile's efficient and low-consumption C13 all-aluminum engine, delivering a maximum torque of 121 N·m and a maximum power of 69 KW. 2. Safety: It features a compact cage-type body structure, high-strength steel body, 4-door anti-collision beams, and other designs, along with ABS+EBS, dual airbags, and a reverse radar, further ensuring safety. 3. Interior: The interior adopts a symmetrical wraparound design, providing a sense of inclusiveness and creating a personalized cabin space. It also uses a dual-color scheme with a dark upper and light lower part, flowing naturally. The texture decorations are exquisite and delicate, offering a sense of quality, and creating a relaxed, comfortable, and stylish interior atmosphere.

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How to reset the maintenance light on the Volkswagen New Santana?

Maintenance light reset steps are as follows: 1. Turn off the ignition switch and stop the engine. 2. Press and hold the right button (reset) on the instrument panel with your left hand. 3. While keeping the right button pressed, turn on the ignition switch. 4. Continue holding the "reset" button until the maintenance light enters reset mode, then release the right button (reset button). Within 30 seconds, press and hold the odometer hour reset button for about 3 seconds until all warning messages disappear. 5. Within 20 seconds of releasing the right button, press the left "menu button" once to confirm the reset. Following these steps will clear the maintenance cycle indicator and restore it to normal display mode.

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What are the causes of fluctuating car idle speed?

Car idle speed fluctuations can be caused by intake manifold or various valve leaks, excessive carbon buildup in the throttle body and intake passages, faulty idle air control components, or incorrect signals received by the air intake control unit. Intake manifold or various valve leaks: When unwanted air, fuel vapor, or exhaust gases enter the intake manifold, it leads to either too rich or too lean air-fuel mixture, causing abnormal engine combustion. Excessive carbon buildup in throttle body and intake passages: When there's too much carbon deposit or dirt in the throttle body and surrounding intake passages, the air channel cross-sectional area changes. This prevents the control unit from precisely regulating idle air intake, resulting in improper air-fuel mixture and abnormal combustion. Faulty idle air control components: Malfunctioning idle air control components lead to inaccurate idle air control. Incorrect signals received by air intake control unit: When the air intake control unit receives wrong signals and issues incorrect commands, it causes inaccurate idle air intake control, leading to abnormal engine combustion. This is an indirect cause of unstable idle speed. Solutions for fluctuating car idle speed: When experiencing unstable idle speed, first adjust the idle speed. If the problem persists after adjustment, check whether the idle jet and idle air jet are clogged. If clogged, clean them with gasoline or acetone and blow through with compressed air. If not clogged, stabilize the engine at a certain RPM and listen for air leaks at the intake manifold or carburetor middle/lower gasket areas. If leaks are found, tighten screws or adjust gaskets to resolve. If idle instability is accompanied by reduced engine power, further inspect spark plug conditions, valve sealing performance, and ignition timing. Perform repairs or adjustments if necessary.

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What items are required for Subject 4?

Why does the 10th-generation Civic's AC only blow air without cooling?

Should private cars use water-based or dry powder fire extinguishers?

Where is the engine number stamped on the Wuling Zhiguang?

What is the fuel tank capacity of the Changan Yuexiang V3?

How to reset the maintenance light on the Volkswagen New Santana?

What are the causes of fluctuating car idle speed?

What is the difference between Volvo T4 and T5?

Why does the Sagitar make a buzzing sound when driving at low speeds?

What are the length, width, and height dimensions of the Levin?

How to Identify Battery Quality