What is the content of the Subject 3 driving test?

What Type of Gasoline Should the Buick Envision Use?

The Buick Envision should use 92-octane gasoline, as recommended in the vehicle's official owner's manual. In addition to checking the appropriate gasoline grade in the owner's manual, you can also find it indicated on the fuel tank cap. Typically, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should use 92-octane gasoline, while those with a compression ratio between 10.0-11.5 should use 95-octane gasoline. For higher compression ratios, 98-octane gasoline is recommended. However, with the application of new technologies, the compression ratio alone cannot determine the appropriate gasoline grade, as high compression ratio engines can also be tuned to use lower-octane gasoline. Other factors, such as ignition timing, turbocharging technology, and Atkinson cycle technology, also play a role. Generally, the higher the gasoline octane rating, the higher the octane number and the better the anti-knock performance. 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane. If the Buick Envision occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. However, prolonged use of the wrong gasoline grade can have the following effects: Using a higher-octane gasoline in a vehicle designed for lower-octane fuel will not cause damage, but the increased octane number can alter the fuel's ignition point, leading to delayed combustion in the engine. This reduces the engine's power output and thermal efficiency, resulting in poorer performance. Using a lower-octane gasoline in a vehicle designed for higher-octane fuel can cause engine knocking. The significantly lower octane number lowers the fuel's ignition point, causing premature ignition during the compression stroke. If combustion occurs before the spark plug fires, resistance is created during the upward stroke. This resistance makes the engine run very unevenly. Mild knocking may only increase noise without significant engine damage, but severe knocking indicates serious engine conditions. The vibrations not only affect driving stability but can also cause abnormal wear on the pistons and cylinders, potentially leading to cylinder scoring in severe cases.

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How to Set Up Automatic Door Lock for Toyota RAV4?

Toyota RAV4 automatic door lock setup steps are as follows: 1. Press the one-touch start button below the steering wheel to start the vehicle engine, otherwise the setup cannot be completed. 2. Press and hold the door lock button located on the driver's side armrest. 3. Click the icon button on the right side of the multifunction steering wheel and release it upon hearing a beep sound. 4. At this point, the automatic door lock function is successfully set up. Below is some relevant information about the Toyota RAV4: The RAV4 is the base model in Toyota's compact multipurpose off-road vehicle family, standing for 'Recreational Active Vehicle with 4-wheel drive.' The dimensions of the all-new fifth-generation 2019 Toyota RAV4 are 4600mm in length, 1845mm in width, 1690mm in height, with a wheelbase of 2660mm.

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What is the difference between with ABS and without ABS?

The differences between with ABS and without ABS are as follows: 1. ABS is an anti-lock braking system that can effectively keep the wheels in a rotating state, improving the stability of the car during braking and the braking performance under poor road conditions. 2. ABS continuously detects the speed of each wheel through speed sensors installed on each wheel or drive shaft. The computer calculates the current wheel slip rate, compares it with the ideal slip rate, and makes a decision to increase or decrease the braking pressure. It commands the actuator to adjust the braking pressure in time to keep the wheels in an ideal braking state. 3. Without ABS, when emergency braking is applied, all four wheels will be completely locked, causing skidding and even spinning or fishtailing. 4. ABS can prevent loss of steering control and wheel skidding during emergency braking, ensuring the wheels are not locked during braking. The tires do not rub against the ground at a single point, increasing friction and achieving a braking efficiency of over 90%.

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Should You Engage the Handbrake First or Shift to Neutral First?

When parking, it is generally recommended to shift to neutral first and then engage the handbrake, but the specific situation should be considered. Below are the relevant details: Automatic Transmission Vehicles: For most automatic transmission models, you can either engage the handbrake first or shift to Park (P) first when parking. Operating Principle: Whether to engage the handbrake first or shift to neutral first actually involves two different points of force application. Shifting to neutral first applies force to the locking mechanism of the P gear, which also affects the transmission, while engaging the handbrake first applies force to the handbrake itself, with minimal impact on the transmission. Parking Under Different Conditions: On flat roads, neither method will significantly affect the transmission. You can choose to engage the handbrake first or shift to neutral first. The general procedure is: shift to P gear - release the brake - engage the handbrake - turn off the engine. On steep slopes, the force is applied to the handbrake. The recommended method is: press the brake - shift to neutral - engage the handbrake - turn off the engine - shift to P gear. This approach has relatively less impact on the transmission.

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What are the main components of brake fluid?

Brake fluid is composed of the following components: 1. Component one: Polyglycol ether solvent, approximately two-thirds. Polyglycol has very high viscosity, so polyglycol ether is used to dilute it. Polyglycol ether ensures that the solvent functions properly in the fluid. 2. Component two: Lubricant base fluid, approximately one-third. The base fluid generally refers to polyglycol, used as a lubricant, accounting for about one-third of the brake fluid. These base fluids are obtained through complex chemical reactions of alkylene oxides (ethylene and propylene) with glycol or water. 3. Component three: A small amount of additives. Brake fluid requires the addition of a few additives, such as corrosion inhibitors and antioxidants, which effectively protect the brake system from corrosion, slow down the oxidative decomposition of substances, and limit the formation of acidic decomposition products and resins. Although these additives are added in small quantities, they are crucial and can significantly extend the lifespan.

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What transmission does the Geely Boyue use?

Geely Boyue uses a manual transmission from Germany's Getrag. The DSI6AT, on the other hand, belongs to Australia's DSI Automatic Transmission Company, one of only two independent automatic transmission companies in the world not affiliated with automobile manufacturers. Below is a related introduction: 1. Australia's DSI Automatic Transmission Company is a specialized company engaged in the research, development, manufacturing, and sales of automatic transmissions. In 2009, DSI was wholly acquired by China's Geely Holding Group. Currently, Geely has established factories in Xiangtan, Jining, Chongqing, and other locations for the large-scale production of DSI automatic transmissions, which have been installed in models such as the Emgrand EC8, Englon SC7, and Boyue. The world-renowned automatic transmission component company BorgWarner once wholly owned DSI for 30 years. DSI Automatic Transmission Company has an annual production capacity of 180,000 automatic transmissions, covering four-speed and six-speed front and rear-wheel drive and all-wheel drive high-torque automatic transmissions. It supplies components for world-famous automobile companies, including those in South Korea, and is currently developing advanced eight-speed front and rear-wheel drive automatic transmissions, DCT dual-clutch transmissions, and CVT continuously variable transmissions. 2. The Geely Boyue DSI6AT employs a torque converter with anti-slip control and a lock-up clutch, capable of meeting torque demands of up to 400N·m or even higher, while ensuring sufficient safety margins. The DSI6AT benefits from mature technical quality, accumulated advantages in manufacturing processes, and supporting systems, ensuring reliability in use with a service life of up to 250,000 km.

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What is the content of the Subject 3 driving test?

What Type of Gasoline Should the Buick Envision Use?

How to Set Up Automatic Door Lock for Toyota RAV4?

What is the difference between with ABS and without ABS?

Should You Engage the Handbrake First or Shift to Neutral First?

What are the main components of brake fluid?

What transmission does the Geely Boyue use?

What are the differences between the Mercedes-Benz A180L and A200L?

How to Reset the Maintenance Light on the H6?

Which brand does the Mustang belong to?

How Long Can a Radiator Leak Sealer Last?