What is the Subject 4 Test?

What does BMW GPF mean?

GPF in a car refers to the Gasoline Particulate Filter, which is a ceramic filter installed in the emission system of a gasoline engine. Its main function is to capture particulate emissions before they enter the atmosphere, thereby reducing particles. Below is relevant information: 1. Car GPF indicator light: When the GPF indicator light in the car is on, it means that the particulate matter accumulated in the GPF needs to be cleaned. 2. Arrangement forms: Integrated with TWC for installation, located close to the exhaust manifold, known as close-coupled arrangement; installed directly downstream of the TWC, known as rear-mounted arrangement; applying a three-way catalyst coating on the GPF substrate to form a four-way catalyst.

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How long does gasoline take to deteriorate?

Gasoline shelf life varies from a few months to several years depending on storage conditions and the type of fuel used. There are two key points to note when refilling engine oil: 1. When selecting engine oil: It must strictly comply with the oil grade specified in the vehicle's user manual. If the same grade is unavailable, you may use a higher-grade oil, but never substitute with a lower-grade one; 2. When adding engine oil: The oil quantity should be slightly below the standard mark. Excessive oil increases crankshaft rotation resistance, reduces engine output power, and may cause oil to enter the combustion chamber, leading to oil burning, blue smoke emission, and increased fuel consumption.

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Is it normal for a car to drip water without the air conditioning on?

It is normal for a car to drip water without the air conditioning on. This could be due to the evaporator in the vehicle's air conditioning system being located behind the dashboard. Do not turn on the air conditioning immediately after entering the car: Many car owners are eager to turn on the air conditioning to cool down the interior after getting into a sun-exposed vehicle. However, starting the air conditioning immediately after the engine is running increases the load on the engine. Over time, this can damage the engine. The correct approach is to first open the car doors and windows, start the engine, and allow the accumulated hot air to escape. Once the temperature inside and outside the car is similar, close the windows and doors, turn on the air conditioning, and start the car. This not only lubricates the engine but also enhances the cooling efficiency of the air conditioning, achieving two benefits at once. Alternate between internal and external air circulation: Many people worry that using external air circulation will let the cold air escape and consume more fuel, so they keep the internal air circulation on even during long trips. However, prolonged use of internal air circulation can make the air inside the car increasingly stale, leading to dizziness and a feeling of oxygen deprivation over time. When the air conditioning is first turned on, always start with external air circulation. After the temperature has decreased, switch to internal air circulation. Then, periodically alternate between internal and external air circulation to maintain air quality. Do not just turn on the air conditioning and leave it at that.

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What is the complete process of the driving test simulation for Subject 3?

Subject 3 driving test simulation involves the following steps: simulating nighttime driving scenarios with light usage test, starting the vehicle, changing lanes, driving straight, passing through pedestrian crossings, passing through school zones, passing through bus stops, passing through intersections, meeting oncoming vehicles, overtaking, making U-turns, and pulling over to park. Below are the precautions to take before starting the vehicle: 1. Turn on the turn signal: Before starting, you must turn on the turn signal and wait for it to flash for 3 seconds before moving the vehicle or steering wheel. After turning on the signal, you should also observe the road conditions; failure to do so will result in an immediate deduction of 100 points. 2. Check the doors: Before starting, you should also check if the doors are closed. Starting the vehicle with the doors open will also result in an immediate deduction of 100 points.

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What are the symptoms of transmission vibration?

The symptoms of transmission vibration include feeling vehicle shaking during low-speed acceleration and hearing abnormal knocking sounds. The main causes of transmission vibration are: excessive carbon deposits, dirty throttle body or air filter, spark plug failure, and aging engine components. The details are as follows: 1. Spark plug failure causing misfire: This is the most common reason for engine vibration. The problem lies in the engine ignition coil or spark plugs. If the ignition coil malfunctions or spark plugs fail to fire for some reason, the vehicle will experience shaking. Misfire is relatively easy to diagnose - if the vehicle shakes noticeably more than usual during medium-low speed operation and feels sluggish during acceleration, it can basically be determined as engine misfire. 2. Excessive carbon deposits: Too much carbon buildup inside the engine will absorb some fuel during startup, leading to an overly lean air-fuel mixture. The engine only begins normal operation after the carbon deposits become saturated with gasoline. However, when the mixture is ignited, the gasoline absorbed by carbon deposits gets sucked back into the cylinders by vacuum pressure, creating an overly rich mixture. This alternating lean-rich condition causes engine vibration. 3. Dirty throttle body or air filter: A severely dirty air filter restricts sufficient air intake into engine cylinders. The imbalanced air-fuel mixture results in insufficient engine power and vibration. A dirty throttle body may not close properly, causing an overly lean mixture during idle and consequent power loss. 4. Aging engine components: If the engine doesn't vibrate or vibrates only slightly when the hood is opened, the problem isn't the engine itself but worn-out buffer components. Commonly, aged engine mounts fail to provide proper cushioning. Timely replacement is necessary after identifying the faulty parts.

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Where Should the Front of the Car Be When Reversing into a Parking Space?

When reversing into a parking space, the front of the car should be aligned with the white solid line. Here are some precautions to take when reversing: 1. Reverse from the left side: It is advisable to reverse from the left side as it provides better visibility for the driver. During the reversing process, first check the rear, then pay attention to both side mirrors. 2. Observe the area behind the car: Before reversing, assess the situation behind the car, estimate the reversing path, and determine if the front of the car might hit any obstacles. Especially when turning the steering wheel sharply, the turning radius of the front wheels is larger than that of the rear wheels, causing the front of the car to swing outward more significantly. Be extra cautious to avoid scraping the front of the car.

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What is the Subject 4 Test?

What does BMW GPF mean?

How long does gasoline take to deteriorate?

Is it normal for a car to drip water without the air conditioning on?

What is the complete process of the driving test simulation for Subject 3?

What are the symptoms of transmission vibration?

Where Should the Front of the Car Be When Reversing into a Parking Space?

Are Airbags for Isolation or Individual Protection?

Can You Simply Let Go of the Steering Wheel When Returning from a Turn?

What RPM is considered aggressive driving when starting with a CVT?

Should Tires Be Changed in Summer or Winter?