What are the contents of Subjects 1, 2, 3, and 4?

What is the method for replacing coolant in the Regal?

Regal coolant replacement method is: Before completely replacing the coolant, conduct a thorough inspection first to check for any signs of leakage or cracks in the pipes, with a focus on examining the five-way water pipe. The five-way pipe gets its name from having five connecting interfaces to various parts. The coolant flows through the five-way pipe and is then distributed to different parts of the car to function. If there is any sign of coolant leakage in this part, the water pipe should be replaced or the interface re-secured as needed. Drain the old coolant, then flush the liquid channels with clean water. Add clean water to the coolant reservoir, then continue to pour water into the reservoir to allow it to flow continuously through the engine cooling system. Start the engine and let it idle for 3 to 5 minutes to circulate the water. The water initially flowing out of the reservoir will be slightly pinkish. Continue adding clean water until the water coming out is clear. Note: Don’t forget to remove the heater hose and drain the water from the heater core. After draining for about an hour, add the new coolant through the radiator hose. This is a method to allow the coolant to flow quickly into the radiator. Then, add another container of coolant to the coolant reservoir until it is nearly full. Start the engine and let it run for about 10 minutes. At this point, as some air is expelled from the cooling system, the liquid level will drop. Add more coolant until it reaches the maximum mark "MAXT" on the reservoir.

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How to Reset the Maintenance Light on BMW 740?

BMW 730 Maintenance Light Reset 1. Turn on the ignition. 2. Press and hold the "Reset" button located at the bottom left of the instrument panel until the first maintenance item is displayed on the instrument panel screen. 3. Press the "Reset" button once to switch to the next maintenance item. There are a total of 9 maintenance items. 4. Switch to the maintenance information interface you want to reset, then press and hold the "Reset" button until the display shows the "Reset?" prompt. 5. Press and hold the "Reset" button for more than 3 seconds again. A pop-up will appear showing that the information is being reset, along with a reset progress bar at the bottom. Once the progress bar completes, the reset is finished. The BMW 7 Series is BMW's flagship luxury sedan series, featuring a 4-door sedan body style and a front-engine, rear-wheel-drive layout. The BMW 7 Series is the brand's premium model, exclusively available in sedan form. It is produced only in Germany by BMW and replaced the previous BMW New Six model in 1977. The BMW 7 Series is equipped with numerous cutting-edge and sophisticated technologies. Since the launch of the first generation in 1977, each update has represented an evolution beyond perfection, setting new standards in design, performance, and innovation. It perfectly combines pure driving pleasure with luxurious comfort.

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What Causes the Clicking Sound from the Chassis After Parking?

The reason for the clicking sound from the chassis after parking is: After prolonged driving, the temperature of the exhaust system becomes very high, especially the three-way catalytic converter, which typically operates at temperatures between 400-800 degrees Celsius. When the car is parked and rapidly cools down, thermal contraction occurs, resulting in a "clicking" sound. The same principle applies to the exhaust pipe, so this is a normal phenomenon. More details are as follows: 1. During a cold start of the car, you may hear a "clicking" noise from the engine compartment. This sound is actually caused by the fuel pump not yet establishing sufficient oil pressure during the cold start, leading to inadequate lubrication of components. Normally, this clicking noise will disappear after the engine runs for a while. 2. There are also some abnormal clicking sounds, such as those caused by aging or loosening engine mounts or an overly rich air-fuel mixture. Engine mounts are rubber blocks placed between the engine and the frame. Their purpose is to reduce vibration and cushion the engine's operation while securing the engine in place. If these mounts become aged or loose, the engine may shake, and in severe cases, a "clicking" noise may occur. This can usually be resolved by replacing the engine mounts. 3. When the engine's air-fuel mixture is too rich, symptoms include difficulty accelerating after starting, uneven engine operation, black smoke from the exhaust pipe, a clicking noise from the engine, and sometimes backfiring. Engine power decreases, and fuel consumption increases. This is often related to carbon buildup or clogged filters and usually does not require major repairs.

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What are the causes of piston slap after an engine overhaul?

Engine overhaul after the production of piston slap causes are: piston and cylinder with excessive clearance, piston direction installed in reverse or piston deformation, cylinder wall lubrication is poor, lubrication conditions are poor, oil pressure is low or oil viscosity is too low, connecting rod bending or twisting deformation, piston connecting rod group assembly makes the piston in the cylinder tilt exceeds the allowable range, etc. The specific causes of piston slap after an engine overhaul are as follows: 1. Due to improper repair, the piston and cylinder fit clearance is too large, or because the cylinder wear is serious, the clearance is too large, the engine at low temperature when the piston clearance is large, the piston slap noise is serious, the engine temperature rises after the piston expansion, making the piston fit clearance smaller, the piston slap noise is reduced or disappeared. 2. The piston direction is installed in reverse or the piston is deformed, destroying the normal clearance between the piston and the cylinder, resulting in piston slap noise. 3. The cylinder wall lubrication is poor, the lubrication conditions are poor, the oil pressure is low or the oil viscosity is too low, the piston and the cylinder wall can not form a normal oil film, the piston and the cylinder directly collide and produce piston slap. 4. The connecting rod is bent or twisted and deformed, and the assembly of the piston connecting rod group causes the piston to tilt in the cylinder beyond the allowable range. Not only does it make the sealing worse and the lubrication conditions worse, but it also causes abnormal wear of the cylinder, which causes the piston and the cylinder wall to collide and produce noise.

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How to Fold Down the Rear Seats of the Hongqi H5?

First, open the trunk and observe that there are two levers on the rear seats. Pulling them will allow you to fold down the rear seats. The split-folding rear seats mean that the backrests can be folded down in proportion. Compared to folding down the entire rear seat, the split-folding method offers greater flexibility, allowing you to fold down only half of the backrest to accommodate large items while the remaining part can still be used for seating. More details are as follows: 1. Split-folding rear seats refer to the backrests that can be folded down in proportion. Compared to folding down the entire rear seat, the split-folding method provides higher flexibility, enabling you to fold down only half of the backrest to place large items while the unfolded part can still be used for seating. Common split-folding ratios include: 1/3, 2/3, and 1/2. 2. 1/3:2/3 split-folding: This usually appears in rear seats with three seats, allowing you to fold down two seats on one side or one seat on the other side. 1/2 split-folding: This typically appears in rear seats with two seats, allowing you to fold down one of the two seats. 3. Entire rear seat folding means the backrest of the rear seat is a single unit. When you need more space for large objects, you can fold down the entire rear seat backrest to gain additional space. The downside of entire rear seat folding is that when the rear seats are folded down, they cannot be used for seating.

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Where is the rearview mirror heating switch on the Changan UNI-T?

The rearview mirror heating switch is located next to the exterior rearview mirror adjustment button, which is a rectangular button with three wavy arrows. The rearview mirror heating function is particularly useful in rainy or snowy weather. When activated, the heater behind the mirror quickly warms the mirror surface, gradually removing rainwater or fog, eliminating the need for the driver to frequently wipe the mirror manually, thereby reducing driving hazards. Principle of the rearview mirror heating function: After pressing the button, the electric heater behind the rearview mirror glass rapidly heats up to a fixed temperature within a few minutes, typically between 35-60 degrees Celsius. The heat is distributed across the left and right rearview mirrors. Simultaneously, as the temperature rises and evaporation occurs, water droplets on the mirror surface become smaller, and fog gradually dissipates, effectively defogging and deicing the mirror. However, if the rain is particularly heavy, the effect may diminish and become less noticeable. Precautions for using the rearview mirror heating function: The principle of rearview mirror heating involves adding electric heating wires to the mirror. These wires consume a significant amount of electricity. Therefore, when using the rearview mirror heating function, ensure the car is in an active state. Avoid activating the heating function while the car is stationary to prevent draining the car battery, which could lead to insufficient power for starting the vehicle. Other methods for defogging rearview mirrors include: Opening windows for air circulation: Crack open the side windows slightly to allow air exchange between the inside and outside of the car. This reduces the temperature difference, causing the fog to dissipate gradually. Adjust the car's air conditioning to the appropriate setting to blow warm air for defogging.

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What are the contents of Subjects 1, 2, 3, and 4?

What is the method for replacing coolant in the Regal?

How to Reset the Maintenance Light on BMW 740?

What Causes the Clicking Sound from the Chassis After Parking?

What are the causes of piston slap after an engine overhaul?

How to Fold Down the Rear Seats of the Hongqi H5?

Where is the rearview mirror heating switch on the Changan UNI-T?

How Long Does It Take to Study for Subject 1?

The Impact of Not Replacing Spark Plugs on a Vehicle

Why does the Changan engine shake excessively during cold start?

How much fuel can a Changan Oshan X7 tank hold?