Should You Start the Engine or Turn on the Turn Signal First in Subject 3 Driving Test?

Why Can't the Key Be Pulled Out in an Automatic Transmission Car?

Automatic transmission cars may fail to release the key because the gearshift is not properly returned to the P (Park) position. After turning off the engine, if the gearshift does not fully return to the P position and fails to trigger the electronic sensor, the owner should check for any obstructions in the gear slot. After removing any obstructions, start the car and shift the gear again to ensure it is fully returned to the P position, allowing the key to be pulled out. Automatic transmission cars may also experience situations where the key cannot be turned. This is due to the car's steering wheel auto-lock feature, a security function. It usually occurs when the steering wheel is inadvertently turned left or right while parking and turning off the engine, or if the wheels are not aligned properly. Force applied to the steering wheel can activate the auto-lock, causing the steering lock pin to engage with the steering column, making the steering wheel immovable and the key unable to turn. In this case, while gently turning the key with the right hand, use the left hand to wiggle the steering wheel left and right, which should allow the key to turn.

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Does Lower Fuel Consumption per 100 km Mean More Fuel Efficiency?

The lower the fuel consumption per 100 kilometers, the more fuel-efficient the car is. The fuel consumption per 100 kilometers is a key indicator to measure whether a car is fuel-efficient, and it is usually displayed on the car's dashboard. The comprehensive fuel consumption per 100 kilometers is not fixed; in addition to being affected by the car's engine displacement, it is also influenced by other factors, resulting in some fluctuations. Fuel consumption per 100 kilometers refers to the amount of fuel consumed by a car traveling 100 kilometers, which is an important parameter of a car. The fuel consumption per 100 kilometers published by the Ministry of Industry and Information Technology is a comprehensive data obtained under certain conditions and at a certain speed. The fuel consumption per 100 kilometers published by the Ministry of Industry and Information Technology is an ideal value, and the actual fuel consumption is often higher than this value. Fuel consumption per 100 kilometers = fuel consumption (liters) ÷ distance traveled (kilometers) × 100. The usual calculation method is to fill up the fuel tank when the fuel gauge light comes on, reset the trip odometer to zero, and then record the trip odometer when the fuel gauge light comes on again. The number of liters of fuel added divided by the distance traveled and then multiplied by 100 gives the fuel consumption per 100 kilometers. Fuel consumption per 100 kilometers is an indicator of a vehicle, while working condition fuel consumption is a standardized statistical specification. The slower the vehicle travels within the economic speed range, the higher the fuel consumption per 100 kilometers. Beyond the economic speed, the opposite is true. If the engine speed is controlled within the same safe speed range, regardless of the vehicle's speed, the hourly fuel consumption is the same. When calculating fuel consumption for highways and engineering transportation, the first two specifications are not suitable, and calculating by hourly fuel consumption is more accurate. The formula for hourly fuel consumption is: fuel consumption per 100 kilometers / 100 * limit * 0.8 (the limit speed is the highest safe speed).

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What is Engine Compression Ratio?

Engine compression ratio is the ratio of the volume of the cylinder before compression to the volume of the compressed air-fuel mixture, which is the ratio of the maximum volume of the cylinder when the piston is at the bottom dead center to the volume of the cylinder when the piston is at the top dead center. Engine operation process: Engines operate on a four-stroke cycle, consisting of intake, compression, power, and exhaust strokes. During the intake and power strokes, the piston is at the bottom dead center position, while during the compression and exhaust strokes, the piston is at the top dead center position. For example, if the cylinder volume is 10 when the piston is at the bottom dead center and the compressed mixture volume is 1 when the piston is at the top dead center, the engine compression ratio is 10:1. Impact of compression ratio on engine performance: Higher engine compression ratio: If the engine has a higher compression ratio, the air-fuel mixture is compressed under greater pressure and at a relatively higher temperature. The gasoline in the mixture vaporizes more completely and is easier to ignite. When the spark plug fires after full compression, more energy is released in a very short time. This energy is then transmitted to the wheels through the piston, crankshaft, and other mechanisms, becoming the driving force for the car. Lower engine compression ratio: In engines with a lower compression ratio, gasoline molecules do not vaporize completely. Therefore, after the spark plug fires, the combustion speed is relatively slower, and some energy is converted into heat, causing the engine temperature to rise instead of being fully converted into the car's kinetic energy. Thus, for the same cylinder volume, a higher compression ratio results in greater power output. The engine compression ratio is not the higher the better, but should be appropriate. An excessively high compression ratio can reduce stability and shorten the engine's lifespan.

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Will points be deducted for the driver touching the passenger's chest?

Points will be deducted. During driving, using the right hand to touch the thigh or chest of the passenger in the front passenger seat is an extremely dangerous driving behavior. Frequent vehicle inspection: To ensure driving safety, it is best to conduct a general inspection around the vehicle before each trip, checking for any tire deflation, obstructions on the license plate, whether the rearview mirrors are properly adjusted, and testing the brakes for any issues. Also, periodically check the water level in the radiator over longer intervals. Pay attention to road conditions: While driving, always maintain a clear mind and stay alert to road conditions, prioritizing safety above all. Remember not to show off, overtake recklessly, and adopt the attitude of "preferring to wait three minutes rather than rush a second."

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What are the effects of leaving the car air conditioning on overnight after the engine is turned off?

Leaving the car air conditioning system on after the engine is turned off can affect the vehicle's engine and battery. When the vehicle is started again, the air conditioning system will automatically turn on. This increases the load on the engine during startup, leading to an excessively high power load at the moment of ignition. Prolonged use in this manner can accelerate wear and tear on engine components, cause excessive carbon buildup in the engine, and severely deplete the battery, thereby reducing the vehicle's lifespan. After the engine is turned off, the air conditioning system relies on the battery's stored power. If the battery's stored power is completely drained, the battery will be depleted, making it impossible to start the vehicle. Car air conditioning cools by operating the air conditioning pump, which is powered by the rotation of the engine's crankshaft. When the engine is turned off, the crankshaft stops rotating, so the air conditioning pump ceases to function, and the air conditioning will not cool. Car air conditioning heats by transferring heat from the engine's coolant to the heater core inside the evaporator box, which is then blown out through the air conditioning ducts by the blower. When the engine is turned off, there is no heat to transfer to the heater core, so the air conditioning cannot provide heat.

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Is Car Sticker Decoration Illegal?

Car sticker decoration is not illegal as long as the area covered does not exceed 30%. However, car sticker decorations need to be registered at the vehicle management office. The following precautions should be noted for car stickers: Car stickers must not affect safe driving. According to Chinese laws and regulations, if the spraying, labeling, or body advertisements on a motor vehicle affect safe driving, a fine will be imposed. Car stickers cannot use the special colors designated for specific vehicles. The law stipulates that although vehicle owners can modify the body color, special colors such as fire engine red, engineering rescue yellow, and the upper white and lower blue combination for national administrative law enforcement are reserved for specific vehicles and cannot be used on ordinary vehicles. The area covered by body stickers must not exceed 30% of the total body area. If it exceeds this limit, approval is required. If the area covered by body stickers is too large, exceeding 30% without approval from the public security traffic management department, it will result in inconsistency between the vehicle and the driver's license photo, constituting illegal vehicle modification, and a fine will be imposed.

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Should You Start the Engine or Turn on the Turn Signal First in Subject 3 Driving Test?

Why Can't the Key Be Pulled Out in an Automatic Transmission Car?

Does Lower Fuel Consumption per 100 km Mean More Fuel Efficiency?

What is Engine Compression Ratio?

Will points be deducted for the driver touching the passenger's chest?

What are the effects of leaving the car air conditioning on overnight after the engine is turned off?

Is Car Sticker Decoration Illegal?

Why are there many small dots on the car film?

What Does Negative Fuel Consumption Credit Mean?

Which is better, direct injection or multi-point electronic injection?

What gear should an automatic transmission car be in when towing?