What refrigerant is used in air conditioning?

Why is the engine exhaust pipe black?

The reasons for the blackening of the exhaust pipe are as follows: 1. Poor fuel quality. The quality of fuel directly affects the working efficiency of the engine, and a large amount of impurities not only hinder the normal operation of the engine but also serve as a source of blackening. 2. Insufficient mixing of fuel and air. Inadequate mixing leads to uneven combustion, naturally resulting in incomplete combustion. 3. Turbocharged direct-injection engines are relatively more prone to blackening. Due to the high speed of the turbocharger in turbocharged engines, the mixture of fuel and air varies significantly before and after the turbo kicks in, making it difficult to control the concentration of the air-fuel mixture. Poor adjustment can cause some fuel to burn incompletely, leading to blackening. 4. Faulty catalytic converter. If the catalytic converter is damaged, its secondary oxygen sensor cannot provide accurate data to the engine control unit, causing the air-fuel mixture to become either too lean or too rich. Particularly when the mixture is too rich, symptoms such as increased fuel consumption, incomplete combustion, and severe carbon buildup in the cylinders and spark plugs may occur.

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What to Do When the Car Door Squeaks While Opening and Closing?

Car parts between the door and the body may require lubrication over time. Here is relevant information: 1. The car door and body are connected by hinges, similar to a household door. It is normal for hinges to make noise after prolonged use. To ensure the smooth and silent operation of the hinges, it is recommended to apply lubricant every 2-3 months for maintenance. Additionally, there is another component connecting the door and the body, known as the door limiter. As the name suggests, it is used to restrict the degree to which the door can open—first, to limit the maximum opening angle, and second, to maintain a certain opening angle. 2. If the car has been in use for some time, it is advisable to check whether the door seal has aged. Since the seal is made of rubber, it will gradually deteriorate and wear out over time, leading to noticeable wind noise and friction sounds for passengers. If the seal is aged or damaged, it is recommended to replace it directly. Also, regularly clean the dust and rainwater from the gaps in the seal during daily use to prevent aging.

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What brand is stek?

One of the largest suppliers of automotive paint protection films in the world. Here are the details: 1. Introduction: STEK was founded in 1977 and is headquartered in Seattle, USA. As a company with over 40 years of experience in various protective films, STEK's products cover mobile phones, tablets, screens, window films, architectural films, and automotive paint protection films. In its early development, STEK collaborated with automobile manufacturers to develop OEM clear paint protection films, passing the testing standards of major car manufacturers, thereby establishing its R&D and production capabilities in the field of automotive paint protection films and becoming one of the largest suppliers of automotive paint protection films in the world. 2. Development: As one of the largest suppliers of automotive paint protection films in the world, STEK has its own R&D team and laboratory and collaborates with world-class material manufacturers to develop new products at any time. As a rare manufacturer that combines R&D and production capabilities, STEK, in addition to collaborating with automobile manufacturers, is also committed to developing STEK-exclusive brands and terminal stores, as well as OEM cooperation models.

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Do I need to pay for the Subject 2 test reservation?

For the first attempt at the Subject 2 driving test, no additional payment is required as all fees are already included in the driving school tuition. However, if you fail the Subject 2 test and need to retake it, a fee will be charged. Below are relevant details: 1. Test Subjects: The Subject 2 test includes five mandatory items: reversing into a garage, parallel parking, stopping and starting on a slope, turning at a right angle, and driving through curves (commonly known as S-turns). Some regions may have a sixth item: high-speed card collection. 2. Subject 2 Test Tips: If the car is not aligned when reversing into the garage, check the rearview mirror and steer towards the wider side, but avoid large adjustments—make slight corrections and quickly straighten the wheel. If you are about to cross the line when stopping on a slope, check the right rearview mirror and steer slightly to the left, then quickly straighten the wheel.

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What is the minimum speed for overtaking in Subject 3?

There is a speed limit for overtaking in Subject 3, with a maximum speed of 40 km/h. It is generally recommended to maintain a speed of around 35 km/h, using the third gear. 1. Subject 3 includes the road driving skills test and the safety and civilized driving knowledge test, which are part of the motor vehicle driver's license assessment. It is the abbreviation for the road driving skills and safety and civilized driving knowledge test in the motor vehicle driver's examination. The content of the road driving skills test varies depending on the type of vehicle being licensed. 2. The road driving skills test for Subject 3 generally includes: preparation before driving, simulated lighting test, starting, driving in a straight line, gear shifting operations, changing lanes, parking by the roadside, driving straight through intersections, turning left at intersections, turning right at intersections, passing pedestrian crossings, passing school zones, passing bus stops, meeting oncoming vehicles, overtaking, making U-turns, and driving at night.

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Do I Need to Engage the Handbrake When Restarting the Engine in Subject 2?

No, you don't need to engage the handbrake. First, press both the brake and clutch pedals simultaneously to prevent the vehicle from rolling backward. Then, shift the gear to neutral and turn the key to restart the engine. Below are some relevant details: 1. Reasons for stalling: Releasing the clutch too quickly or lifting it too high is a common mistake made by many trainees. Whether during hill start or other maneuvers, the clutch operation should follow the principle of 'quick press, slow release, and coordinated movement'. Pressing should be quick, but releasing should be slower to accurately feel the semi-engagement point. 2. Retaking Subject 2: If you fail the Subject 2 test on your first attempt, you can retake it once. If you choose not to retake or fail the retest, the current test session ends, and you must reschedule the test after ten days. Within the validity period of the driving skill test permit, the number of test rescheduling for Subject 2 and Subject 3 road driving skills tests must not exceed five times. If you fail the fifth attempt, all previously passed subjects will be invalidated.

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What refrigerant is used in air conditioning?

Why is the engine exhaust pipe black?

What to Do When the Car Door Squeaks While Opening and Closing?

What brand is stek?

Do I need to pay for the Subject 2 test reservation?

What is the minimum speed for overtaking in Subject 3?

Do I Need to Engage the Handbrake When Restarting the Engine in Subject 2?

What car has a logo with two semicircles?

Should the clutch be fully released on a downhill slope in Subject 2?

How long after failing Subject 3 can you schedule the next attempt?

How to fold the side mirrors on both sides of the vehicle?