How to Choose Between Mercedes-Benz C and Audi A4L?

What is the width of a single lane on the highway?

For highways designed with a speed of 120km/h, the lane width is 3.75m, and the emergency stopping lane width is 3.5m. Here are the relevant details: 1. Article 78: Highways shall indicate the speed limit for each lane, with the maximum speed not exceeding 120 kilometers per hour and the minimum speed not less than 60 kilometers per hour. On highways, the maximum speed for small passenger vehicles shall not exceed 120 kilometers per hour, for other motor vehicles it shall not exceed 100 kilometers per hour, and for motorcycles it shall not exceed 80 kilometers per hour. 2. For two lanes in the same direction: the minimum speed for the left lane is 100 kilometers per hour; for three or more lanes in the same direction, the minimum speed for the leftmost lane is 110 kilometers per hour, and for the middle lane it is 90 kilometers per hour. If the speed indicated by road speed limit signs is inconsistent with the above lane speed regulations, the speed indicated by the road speed limit signs shall be followed.

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What Causes Compressor Failure?

Compressor failure may be caused by liquid refrigerant entering the compressor, resulting in liquid compression, or poor oil return to the compressor. Below are detailed explanations of compressor failure: Liquid compression inside the compressor: When liquid refrigerant enters the compressor, it causes liquid compression, leading to the breakage of the scroll. As the liquid refrigerant enters the compressor chamber and undergoes compression, the incompressibility of the liquid exerts extreme lateral shear forces on the scroll, causing the fixed and orbiting scrolls to break and the compressor to seize. The solution is to immediately close the compressor's suction shut-off valve and stop the liquid supply by closing the expansion valve. Poor oil return to the compressor: Poor oil return (oil shortage) in the system prevents the compressor from delivering sufficient oil to all lubrication points. This causes friction at each lubrication point to intensify progressively from bottom to top. The friction leads to overheating of the orbiting scroll bushing, eventually causing it to burn out or even seize. In severe cases, the bushing may experience significant wear and breakage. It is essential to promptly check and replenish the compressor oil.

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What Are the Hazards of Idling for 2 Hours to a Car?

Idling for 2 hours can cause several hazards to a car, including carbon buildup, excessive fuel consumption, and damage to the catalytic converter. The specific hazards are as follows: Carbon Buildup: If the engine runs at idle for a long time, the throttle opening will be very small, and the fuel injector will spray highly concentrated fuel to keep the engine running. Therefore, idling itself is more likely to cause carbon buildup compared to driving or highway speeds. Prolonged idling will inevitably lead to more severe carbon buildup in the engine, directly affecting the car's power and comfort. Excessive Fuel Consumption: According to tests, idling for three minutes consumes fuel equivalent to driving one kilometer. This means that idling for 2 hours can consume almost 2–3 liters of fuel. Catalytic Converter Damage: Prolonged idling results in an overly rich air-fuel mixture in the engine, leading to low oxygen content in the exhaust gases. The unburned mixture may combust at the catalytic converter, which can easily damage it.

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What Causes the Vehicle to Shake When Shifting from D to R Gear?

The shaking may be caused by the following three reasons: 1. The engine or transmission mount rubber is broken or damaged, causing the engine or transmission to not be properly connected and cushioned, resulting in vibration when shifting gears. 2. The engine ignition system or intake system is not functioning properly, causing unstable engine speed and leading to vehicle vibration. However, after reading the data stream of the faulty vehicle's engine, all data indicators show normal, the engine speed is very stable, and the speed needle does not swing back and forth with the vibration. Therefore, this possibility can basically be ruled out. 3. The transmission's lock-up clutch is not working properly, causing a rigid connection of the torque converter, thus leading to vibration. But after reading the data stream of the faulty vehicle's transmission, all data indicators are normal, and the torque converter slip value of the transmission is within the normal range. Additionally, if the lock-up clutch is abnormally engaged, the engine speed needle would also swing back and forth when the vehicle shakes. Therefore, it can be preliminarily judged that the fault of this vehicle should not be caused by damage to internal components of the transmission.

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What is the difference between D and S gears in an automatic transmission?

The following are the differences between D gear and S gear: 1. D gear stands for Drive gear. The advantage of D gear is that it is more fuel-efficient compared to S gear, but the disadvantage is that it provides less power. 2. S gear is the Sport mode, where the engine runs at higher RPMs, and the transmission shifts up later and down earlier. The advantage of S gear is better vehicle performance, while the disadvantage is poorer fuel economy. It is suitable for overtaking or climbing hills. Below are the methods for switching between different gears in an automatic transmission: 1. Shifting from P to R or R to P requires pressing the shift lock and applying the brake. 2. Shifting from R to N does not require pressing the shift lock or applying the brake. 3. Shifting from N to R requires pressing the shift lock and applying the brake. 4. Shifting from N to D requires pressing the shift lock and applying the brake. 5. Shifting from D to S requires pressing the shift lock, but neither releasing the throttle nor applying the brake is needed. 6. Shifting from S to D can be done by directly pushing the lever, without releasing the throttle or applying the brake.

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What Causes the Engine Light to Come On in a Car?

Engine light illumination can be caused by sensor issues, turbocharging problems, or exhaust system malfunctions. Below are the specific reasons for the engine light coming on: Sensor Issues: Sensors include coolant temperature, crankshaft position, air flow, intake air temperature, and oxygen sensors. When these sensors are damaged, have poor connections, or experience signal interruptions, the vehicle's ECU cannot accurately obtain engine data, triggering the engine warning light. Turbocharging Problems: Intake boost piping and turbochargers can also cause the engine warning light to illuminate. The most common issue is turbocharger damage, often accompanied by symptoms such as oil leaks, excessive oil consumption, reduced power, metallic noises, or blue/black smoke from the exhaust. Exhaust System Issues: Components include rear oxygen sensors, catalytic converters, exhaust camshafts, and bearings. The most frequent cause is catalytic converter failure. Factors leading to catalytic converter malfunction include using leaded gasoline, lead/silicon-based lubricant additives, physical damage to the converter, or fuel system failures.

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How to Choose Between Mercedes-Benz C and Audi A4L?

What is the width of a single lane on the highway?

What Causes Compressor Failure?

What Are the Hazards of Idling for 2 Hours to a Car?

What Causes the Vehicle to Shake When Shifting from D to R Gear?

What is the difference between D and S gears in an automatic transmission?

What Causes the Engine Light to Come On in a Car?

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