Can You Pass Subject 4 Without Preparation?

How much fuel is consumed when idling with the air conditioning on for one hour?

When idling with the air conditioning on, fuel consumption varies depending on the engine displacement, typically ranging from 1.4 to 2.5 liters, with an average of around 1.6 liters. Although the fuel consumption is not excessive, it can be detrimental to the engine, leading to carbon buildup and potential overheating damage to the catalytic converter. Below is an introduction to idling conditions: 1. Normal Idling: When the vehicle is parked and the engine is started, the minimum stable engine speed is referred to as parking idle (the process of the engine transitioning from a cold idle state to a warmed-up idle state is called warm-up or hot start). 2. Driving Idle: When the car is in gear, without pressing the accelerator pedal or releasing it while driving, maintaining the minimum throttle opening, the engine speed matches the parking idle speed, which is referred to as driving idle. 3. Unstable Idling: Unstable idling is one of the most common issues encountered in engine maintenance. If the diagnostic approach is incorrect, it can prolong repair time, reduce efficiency, and even cause the vehicle owner to switch to another repair shop due to impatience.

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Where is the water pump located on the Ford Mondeo?

The water pump on the Ford Mondeo is located next to the crankshaft. Automotive engines widely use centrifugal water pumps, whose basic structure consists of components such as the water pump housing, connecting plate or pulley, water pump shaft and bearings or integrated shaft bearings, water pump impeller, and water seal device. It is a major component of the vehicle. The Ford Mondeo is a mid-size car with dimensions of 4873mm in length, 1852mm in width, and 1470mm in height, with a wheelbase of 2850mm. The front suspension of the Ford Mondeo is a MacPherson independent suspension, and the rear suspension is a multi-link independent suspension. It is equipped with a 1.5T turbocharged engine, delivering a maximum power of 134kW and a maximum torque of 243Nm, paired with a 6-speed automatic transmission.

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Should You Release the Accelerator When Shifting from D to L Gear?

When shifting from D to L gear, you should release the accelerator. This is because the automatic transmission in a car relies on hydraulic pressure for power transfer. During driving, the engine generates a certain load, and shifting gears under load can negatively impact the vehicle. An automatic transmission refers to a system where the driver does not need to manually shift gears; the vehicle automatically selects the appropriate gear based on driving speed and traffic conditions. The correct method to start an automatic transmission car is: 1. Fasten the seatbelt, insert the key, and turn it clockwise to the first position to initiate the vehicle's self-check; 2. After the self-check is completed, turn the key clockwise to the second position, shift into D gear, and release the handbrake and foot brake.

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What does the 205/55r16 tire mean?

205/55r16 is the specification size of a tire, representing a tire section width of 205 millimeters, an aspect ratio of 55, 'r' indicating a radial tire, and 16 meaning it can be mounted on a 16-inch rim. Tire maintenance methods are as follows: 1. Inspection: Pay special attention to the condition of the tires, checking for any debris or foreign objects lodged in them. If found, clean them promptly. If not removed in time, some may automatically fall off during driving, while others may gradually 'erode' the tire, penetrating deeper over time. When reaching a certain extent, they can puncture the tire, leading to rupture, blowout, or air leakage, posing potential dangers. 2. Timely Replacement: During inspection, if the tire valve is found to be made of rubber and has turned dark red, it indicates aging and an inability to maintain good airtightness. Replacement is advisable. 3. Check Balance: During driving, experiences such as collisions, high-speed driving, sharp turns, emergency braking, or crossing obstacles may cause the tire to lose balance. This can result in vehicle deviation, bumpiness, or uneven tire wear (commonly known as 'tire cupping'), affecting driving safety. 4. Check Tire Pressure: Monitoring tire pressure is the most crucial aspect of daily tire maintenance. It is advisable to develop a good habit of checking tire pressure regularly (preferably once a week) to eliminate potential safety hazards in their early stages. Tire pressure should be checked when the tires are cold. This is because driving heats up the tires, increasing the pressure above the actual value. If the pressure of a hot tire is reduced, it will be insufficient once cooled.

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Where to Obtain the Annual Inspection Decal for a New Car?

New car annual inspection decals can be obtained at the vehicle management office and inspection stations designated by the vehicle management office. Nowadays, vehicles can be inspected nationwide, eliminating the need for owners to spend considerable time returning to the registration location. Vehicles can be directly inspected and qualified decals can be applied for in areas other than the registration location, without the need for an out-of-region inspection authorization letter. Vehicle annual inspection refers to a mandatory test for vehicles that have obtained official license plates and registration certificates, equivalent to an annual physical examination for the vehicle according to the safety technical conditions for motor vehicle operation. Its purposes are: 1. Timely elimination of potential safety hazards in vehicles; 2. Encouragement of enhanced vehicle maintenance; 3. Reduction of traffic accidents.

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Why Does Car Glass Frost Over?

Car glass frosts over due to the temperature difference between the inside and outside of the vehicle. When the interior temperature is higher than the outdoor temperature, the car glass comes into contact with the colder external environment, causing moisture inside the cabin to condense on the glass and form frost. Solutions to remove frost from car glass include: 1. Applying anti-fog spray; 2. Using the air conditioning's cooling and dehumidifying function to reduce air humidity; 3. Utilizing the air conditioning's warm air function to minimize the temperature difference and eliminate frost on the windows. Methods to prevent car glass from frosting over include: 1. Applying soapy water, detergent, ethylene glycol, glycerin, or polyvinylpyrrolidone; 2. Coating with thick plastic film and silicon, followed by hydroxyethyl methacrylate siloxane; 3. Applying a solution of carboxymethyl cellulose and salt onto the glass.

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Can You Pass Subject 4 Without Preparation?

How much fuel is consumed when idling with the air conditioning on for one hour?

Where is the water pump located on the Ford Mondeo?

Should You Release the Accelerator When Shifting from D to L Gear?

What does the 205/55r16 tire mean?

Where to Obtain the Annual Inspection Decal for a New Car?

Why Does Car Glass Frost Over?

Should the Mercedes Auxiliary Battery Be Replaced If It Fails?

Where is the Mercedes-Benz electronic parking brake?

Can a Manual Transmission License Drive an Automatic Transmission Car?

What Causes the Engine Start-Stop Light to Illuminate?