How to Shift Gears in the Subject 3 Road Test?

What Causes a Lean Air-Fuel Mixture in Cars?

The main causes of a lean air-fuel mixture are insufficient fuel injection, inaccurate detection of intake air volume by various intake sensors leading to inadequate fuel injection, excessive carbon buildup that absorbs fuel, and failure of the oxygen sensor's closed-loop control. Here are some relevant details: 1. The air-fuel mixture in cars refers to the gaseous mixture of atomized automotive fuel and air. When the concentration of fuel in the mixture is significantly lower than the fixed value, this is referred to as a lean air-fuel mixture. 2. When the mixture is too lean, the combustion speed of the fuel decreases, and some of the mixture's combustion occurs as the piston moves toward the bottom dead center. This portion of combustion not only converts less heat into mechanical work but also loses more heat to the cooling water or radiator through the cylinder walls. Therefore, an excessively lean mixture can cause engine overheating and reduced power output. 3. A lean mixture can also result in higher idle speeds, and when accelerating or releasing the throttle, the engine speed may take longer to return to idle speed.

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Can a Damaged Tire Sidewall Be Repaired?

Tire sidewall damage cannot be repaired; in such cases, it is recommended to replace the tire with a new one. Here is relevant information: 1. Tires are rubber products, and prolonged use leads to aging and wear, necessitating regular replacement. Under normal circumstances, tires installed on a vehicle can last for four years. It is advisable to replace tires every four years. 2. When purchasing new tires, always check the production date, as tires have a shelf life. Typically, unused tires have a shelf life of three years; avoid purchasing tires that have been in storage for over three years. 3. After installing new tires, it is essential to perform a dynamic balance test on each wheel to prevent abnormal vibrations during high-speed driving. Such vibrations can affect the vehicle's stability and handling. 4. Regularly check tire pressure during routine use, as it is crucial for tire performance. Tire pressure should neither be too high nor too low. Excessive pressure reduces tire grip, while insufficient pressure can cause wave-like deformation during high-speed driving, increasing the risk of blowouts and accelerating tire aging.

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What are the solutions for feeling insufficient power after an oil change?

The reasons and solutions for feeling insufficient power after an oil change are as follows: 1. Due to prolonged use, the old oil deteriorated, causing its viscosity to decrease, which reduced the engine's movement resistance. The new oil has higher viscosity than the old one, so you may feel increased fuel consumption or insufficient power. Simply switch back to the original oil. 2. It could be due to the car engine itself, where insufficient engine power is the cause. The engine needs to be inspected. 3. The oil filter might be faulty, clogged, or ineffective. Therefore, it's generally recommended to replace the oil filter along with the new oil. 4. If the engine lubrication system hasn't been cleaned for too long, deposits accumulate. Changing to new oil may flush out some impurities, suspending them in the oil and clogging the oil filter, leading to insufficient power. Cleaning the engine lubrication system will resolve this. 5. Pay attention to the amount of oil added. Adding too much or too little oil can both cause insufficient power, which will improve after the second oil change. Either top up the oil or remove some oil.

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How Many Feet to Use When Driving an Automatic Transmission Car?

When driving an automatic transmission car, you should use only one foot. Do not use your left foot for braking, as it is relatively dangerous. Left-foot braking is a technique typically used by race car drivers. Whether driving a manual or automatic transmission vehicle, the right foot should be used to control both the accelerator and the brake. During normal driving, the left foot should rest on the floor in a standby position, while the right foot controls the accelerator. It is not recommended to use both feet when driving an automatic transmission car. When switching between the accelerator and the brake, avoid lifting your leg. The standard posture involves keeping the heel stationary and pivoting the foot on the heel to press either the accelerator or the brake. Many people tend to lift their foot when switching between the two, which can lead to mistakes if they fail to press accurately when distracted. Precautions for driving an automatic transmission car: During normal economical driving, it is essential to release the accelerator pedal after the engine speed rises to a certain level, then gently press the accelerator again. At this point, you will notice the engine speed decrease, indicating that the transmission has completed the upshift. Developing this habit during daily driving can significantly reduce overall fuel consumption.

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How to Check Car Insurance Information?

You can check vehicle insurance information by: directly calling the insurance company's customer service, accessing the personal center through the insurance company's official public account to enter the policy inquiry page and view policy details; logging into the insurance company's app to check policy information; visiting the insurance company's official website, registering and logging in, then finding the corresponding "policy services" to inquire about the policy; or going to the insurance company's counter in person with relevant documents for inquiry. What to Do If You Lose Your Car Insurance Policy: According to the relevant insurance company's regulations, the policyholder must bring their original ID card, vehicle registration certificate, and other required documents to process the request. Commercial Auto Insurance Policy Replacement: When replacing a commercial auto insurance policy, the insurance company can only provide a copy of the policy. According to laws such as the "Insurance Law" and the "Contract Law," a copy of the commercial auto insurance policy has the same legal effect as the original during claims. Compulsory Traffic Insurance Replacement: As compulsory traffic insurance is mandatory for every car owner, when replacing the compulsory insurance policy, considering issues such as vehicle inspection and annual checks, the policyholder can obtain a replacement original policy but cannot reissue the compulsory insurance decal.

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Will touching the line deduct points in a right-angle turn?

In theory, touching the line with the vehicle body in Subject 2 (off-road driving test) does not deduct points—note that this refers to touching the line, not crossing it. Crossing the line will definitely result in a 100-point deduction. Both right-angle turns and curve driving allow touching the line, as long as the wheels do not press against the road edge line. If the wheels press against the road edge line, 100 points will be deducted. The right-angle turn is an assessment point in Subject 2 of the driver's test, evaluating the driver's ability to correctly operate the steering and accurately judge the inner and outer wheel differences when driving through abrupt road changes. Here’s an introduction to the Subject 2 test: 1. Off-road driving (Subject 2) involves actual vehicle operation and is only graded as pass or fail. 2. It consists of 9 mandatory test items (all without poles), including reverse parking, narrow road U-turns, parallel parking, stopping and starting on a slope, right-angle turns, curve driving, emergency braking, tunnel driving, and toll booth card retrieval. 3. All nine mandatory items must be passed to successfully complete the Subject 2 test.

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How to Shift Gears in the Subject 3 Road Test?

What Causes a Lean Air-Fuel Mixture in Cars?

Can a Damaged Tire Sidewall Be Repaired?

What are the solutions for feeling insufficient power after an oil change?

How Many Feet to Use When Driving an Automatic Transmission Car?

How to Check Car Insurance Information?

Will touching the line deduct points in a right-angle turn?

What is the normal RPM for an automatic transmission car?

Can You Shift from D to N While Driving an Automatic Transmission Car?

Does Idle Start Hurt an Automatic Transmission Car?

What Do the Left and Right Feet Control in an Automatic Transmission Car?