Can you know if you got a question wrong immediately after answering it in the Subject 4 exam?

Is it necessary to clean the car fuel injectors?

Engine fuel injectors do need cleaning for the following reasons: 1. Fuel injectors spray gasoline and have a self-cleaning characteristic. When clogged by gum deposits or carbon buildup, it affects the consistency of fuel flow among injectors or causes fuel dripping. If the flow rate deviation of each injector exceeds 5%, it will worsen emissions, and larger deviations will impact power and fuel consumption. 2. Fuel injectors are not consumable parts and don't require frequent cleaning. Excessive cleaning may lead to premature failure. Generally, if the vehicle is in good condition and using quality fuel, cleaning every 40,000-60,000 kilometers is sufficient. Even with minor clogging, there's no need for excessive concern because impurities can be flushed away and burned off during high-gear acceleration, allowing the car's performance to return to normal.

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What is the fuel consumption per 100 kilometers for a Land Rover Range Rover?

5.0-liter Land Rover Range Rover has a fuel consumption of around 16L per 100 kilometers; the 3.0-liter Land Rover Range Rover has a fuel consumption of around 14L per 100 kilometers. The relevant details about the fuel consumption per 100 kilometers are as follows: 1. The fuel consumption per 100 kilometers refers to the amount of fuel a vehicle consumes when driving a hundred kilometers at a certain speed on the road. It is a theoretical indicator of the vehicle. The fuel consumption per 100 kilometers is a value measured by the manufacturer in an objective environment using a dynamometer installed on the vehicle's chassis, converted into speed parameters, and then calculated by driving at a specified speed to obtain the theoretical experimental fuel consumption data per 100 kilometers for the model. 2. The driver's driving skills, road conditions, and whether the air conditioning is on or not will all affect a vehicle's fuel consumption. Therefore, slight variations in fuel consumption are normal.

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Under which company is Li Auto brand?

Li Auto is a new energy vehicle company founded by Li Xiang in July 2015. Here is relevant information about Li Auto: 1. Li Auto's Changzhou base has an annual designed production capacity of 100,000 vehicles, covering four major workshops: stamping, welding, painting, and assembly. It employs a large number of advanced processes and equipment to ensure that the manufacturing quality of the Li ONE meets luxury brand standards. 2. Li Auto's first product, the Li ONE, was launched on October 18, 2018. It is a smart electric large SUV equipped with leading range-extending electric technology and smart technology, offering family users comfortable 6-seat and 7-seat configurations.

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How to Replace the Camry's Cabin Air Filter?

Correct steps to replace the Camry's cabin air filter: 1. The Camry's cabin air filter is located behind the glove compartment on the passenger side. Open the glove compartment to see the cabin air filter housing, then open this housing to replace the filter. 2. The cover of the cabin air filter housing in the Camry is secured with clips. Simply open the cover to remove the old filter and install the new one. Information about the car's cabin air filter: The cabin air filter is a crucial component of the car's air conditioning system and needs to be replaced regularly. The car's air conditioning system is an important comfort feature. The air conditioning system requires regular cleaning and disinfection, and the cabin air filter also needs periodic replacement. If the air conditioning system is not cleaned and disinfected regularly, it can harbor bacteria, significantly affecting the health of the vehicle's occupants. If the cabin air filter is not replaced for a long time, it can impair the cooling efficiency of the air conditioning system. The car's air conditioning system contains refrigerant, typically r134a in most vehicles, which also requires periodic replacement.

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What is the equivalent displacement of a 1.4T engine?

A 1.4T engine is equivalent to a naturally aspirated engine with a displacement of 1.8-2.0L. Generally, the power output of a turbocharged engine can reach about 1.3-1.5 times that of a naturally aspirated engine with the same displacement. A 1.4T engine is essentially a 1.4L naturally aspirated engine equipped with a turbocharger, resulting in significantly enhanced power. Displacement (Swept-volume) is a specialized term in hydraulic transmission, referring to the volume of fluid intake or exhaust per stroke or cycle. The space between the top dead center and bottom dead center of the piston is called the cylinder displacement. If an engine has multiple cylinders, the sum of the working volumes of all cylinders is referred to as the engine displacement, typically measured in liters (L). Engine displacement is one of the most important structural parameters, more representative of engine size than cylinder diameter and number of cylinders. Many engine performance indicators are closely related to displacement. In China, vehicle classification is based on engine displacement. Micro cars have a displacement ≤1.0L, compact cars range from 1.0-1.6L, mid-size cars from 1.6-2.5L, large cars from 2.5-4.0L, and luxury cars have a displacement >4.0L. Engine displacement determines fuel consumption. Larger displacement engines consume more fuel but also deliver stronger power. However, if a small-displacement engine is poorly matched, it may not be more fuel-efficient than a larger-displacement engine and could even consume more fuel. Small-displacement vehicles are generally cheaper. Micro and compact cars not only have lower vehicle and vessel taxes but also significantly lower fuel consumption and maintenance costs. The "T" stands for turbocharged engine, derived from the English word "Turbo." Typically, if you see "Turbo" or "T" on the rear of a car, it indicates the vehicle is equipped with a turbocharged engine. The primary function of a turbocharger is to increase the engine's air intake, thereby boosting power and torque, making the car more powerful. Installing a turbocharger can increase an engine's maximum power by 40% or more compared to a naturally aspirated version. This means the same engine can output significantly more power after turbocharging. In terms of performance, a 1.4T engine can vary greatly in power and torque output depending on tuning. Its performance is roughly comparable to a 2.0L naturally aspirated engine, but it offers superior low-speed torque, which naturally aspirated engines cannot match. Introduction to Naturally Aspirated and Turbocharged Engines: Naturally Aspirated (abbreviated as NA) is a type of car intake system where air is drawn into the combustion chamber solely by atmospheric pressure without any supercharger. Naturally aspirated engines excel in smooth power delivery and direct throttle response, far surpassing turbocharged engines in these aspects. Turbocharging (Turbo-Boost) is a technology that uses exhaust gases from an internal combustion engine (ICE) to drive an air compressor, thereby increasing the engine's air intake. This enhances the engine's power and torque, making the vehicle more dynamic. After turbocharging, an engine's maximum power can increase by 40% or more compared to its naturally aspirated counterpart. For example, a 1.8T turbocharged engine can deliver performance similar to a 2.4L naturally aspirated engine but with fuel consumption only slightly higher than a 1.8L engine. This improves fuel economy and reduces emissions. However, turbocharging significantly increases the engine's operating pressure and temperature, which can shorten its lifespan compared to a naturally aspirated engine of the same displacement and may affect mechanical and lubrication performance. Turbocharging technology was originally developed for aircraft engines to address insufficient air intake at high altitudes. The turbocharger is the only mechanical device that can increase engine output power without altering its efficiency. A turbocharging system mainly consists of a turbine housing and a compressor. The turbine housing's intake is connected to the engine's exhaust manifold, while the exhaust outlet links to the exhaust pipe. The compressor's intake connects to the air filter pipe, and its outlet attaches to the intake manifold. The turbine and impeller are mounted inside the turbine housing and compressor, respectively, and are rigidly connected on the same shaft.

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Where is the intake port of a motor vehicle engine located?

The location of the intake port of a motor vehicle engine varies depending on the model. Some engine intake ports are located at the front of the engine, while others are at the rear. The position and shape may differ among different vehicles, but one commonality is that they are all within the engine compartment. By opening the hood, the location of the air filter indicates the car's intake port. The primary function of the intake system is to supply the engine with clean, dry, sufficient, and stable air to meet the engine's requirements, while preventing impurities and large particulate dust from entering the engine combustion chamber, which could cause abnormal wear.

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Can you know if you got a question wrong immediately after answering it in the Subject 4 exam?

Is it necessary to clean the car fuel injectors?

What is the fuel consumption per 100 kilometers for a Land Rover Range Rover?

Under which company is Li Auto brand?

How to Replace the Camry's Cabin Air Filter?

What is the equivalent displacement of a 1.4T engine?

Where is the intake port of a motor vehicle engine located?

What is the lifespan of the Lexus ES hybrid battery?

Is the Q3 dual-clutch transmission wet or dry?

Which Button to Press to Clear Windshield Fog?

What is the difference between aftermarket and OEM headlights?