What Causes the Humming Sound After Replacing Old Tires?

Brief Description of How to Replace Automotive Air Conditioning Refrigerant

There are two replacement methods: the high-pressure end charging method and the low-pressure end charging method. Below is a relevant introduction about air conditioning refrigerant: 1. Operating Principle: When the air conditioner operates in cooling mode, the low-temperature, low-pressure refrigerant gas is compressed by the compressor into high-temperature, high-pressure refrigerant gas. The high-temperature, high-pressure refrigerant gas releases heat through the condenser (typically air-cooled, such as the heat-dissipating copper tubes of the outdoor unit) in the outdoor heat exchanger, turning into medium-temperature, high-pressure liquid (heat is removed by the outdoor circulating air). The medium-temperature, high-pressure liquid then passes through the capillary tube, expanding and reducing pressure to become low-temperature, low-pressure liquid. The low-temperature, low-pressure liquid refrigerant absorbs heat and evaporates through the evaporator (indoor unit copper tubes), turning into low-temperature, low-pressure gas (indoor air is cooled as it passes over the heat exchanger surface). 2. Refrigerant Charging Method: Under normal temperature and pressure, R410A is a non-chlorinated fluorinated alkane non-azeotropic mixed refrigerant, appearing as a colorless gas stored in steel cylinders. Based on the characteristics of R410a, an application practice was conducted to replace HCFC22 with R410a in a room air conditioning system, involving theoretical analysis and system matching. Experimental results show that under the same conditions, compared to HCFC22, the heat transfer coefficient increases, flow resistance decreases, and after system optimization and matching design, performance (COP) is significantly improved, reaching the European market's Class A energy efficiency rating.

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How much over the speed limit is driving at 115 km/h in a 100 km/h zone?

Driving at 115 km/h in a 100 km/h zone is considered speeding, exceeding the limit by 15%. The penalties and demerit points for speeding are as follows: 1. Exceeding the speed limit by less than 10%: No penalty for now. 2. Exceeding the speed limit by 10% to less than 20%: Fine and 3 demerit points. 3. Exceeding the speed limit by 20% to less than 50%: Fine and 6 demerit points. 4. Exceeding the speed limit by 50% or more: Fine and 12 demerit points. Relevant information about speeding is as follows: 1. Introduction one: Speeding refers to the behavior of a driver operating a vehicle at a speed exceeding the legal or regulatory limits, for example, the maximum speed on highways should not exceed 120 km/h. 2. Introduction two: When there are speed limit traffic signs or speed limit surface signs, drivers must strictly adhere to the speed indicated. Exceeding the designated speed for that section of the road constitutes speeding.

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How to Upgrade the Navigation System in a Car?

It is best to visit a 4S shop for after-sales service or go to an auto repair shop for the upgrade. Below is some relevant information about car navigation systems: 1. Concept: A car navigation system is a driving assistance device that helps users accurately locate their current position and calculates the route based on a set destination, guiding users to their destination through map display and voice prompts. 2. Operating Principle: GPS consists of three main parts: space satellites, ground monitoring, and user receivers. In space, 24 satellites form a distributed network, each located in one of six quasi-synchronous orbits around the Earth, 20,000 kilometers above the ground with an inclination angle of 55°. Each orbit has four satellites. GPS satellites orbit the Earth every 12 hours, allowing any location on Earth to simultaneously receive signals from 7 to 9 satellites.

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What is the recommended tire pressure for SUVs in winter?

The recommended tire pressure for SUVs in winter is between 2.3 and 2.7 bar, while the standard tire pressure is between 2.2 and 2.5 bar. The hazards of excessive tire pressure include: 1. Reduced friction and adhesion of the tire, affecting braking performance and tire lifespan; 2. Decreased resistance to punctures, increasing the risk of tire blowouts; 3. Accelerated wear on the central tread pattern, shortening tire lifespan, increasing vehicle vibration, and affecting the longevity of other components; 4. Excessive stretching and deformation of tire cords, reducing tire elasticity, increasing the load on the vehicle during driving, and decreasing puncture resistance; 5. Increased susceptibility to punctures from sharp objects like nails and glass, leading to internal cracks, ruptures, and blowouts.

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Why is shifting from P to R gear so tight?

There are two possible reasons. The first is that the car was parked on an uneven surface, and the gear was directly shifted to P before turning off the engine, and then the handbrake was applied. After the engine was turned off, the vehicle moved, causing the P gear to become overly engaged. The correct method should be: stop the car, shift to N gear, apply the handbrake, turn off the engine, and then shift to P gear. The second possibility is that if none of the above operations were problematic, it may be a transmission malfunction. Below are common transmission faults: 1. Oil leakage: Oil seeps from the transmission housing or oil pan, which could be due to aging seals causing poor sealing or manufacturing defects leading to porosity in the housing. 2. Engine stalling when shifting: The engine stalls when shifting to D or R gear, which might be caused by a faulty lock-up solenoid valve or a stuck lock-up control valve. 3. Gear lock-up: Incorrect input or output signals from the transmission or issues with components or wiring may cause this. Sometimes, communication problems between the transmission computer and other system computers can also lead to this issue. 4. No response when shifting: After shifting to D or R gear and releasing the brake, the vehicle does not move. This is often due to damage to the input shaft or reverse clutch, or a faulty D/R brake. 5. Abnormal noises: Unusual sounds from the transmission area while driving are usually caused by worn parts or improper installation of the transmission.

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Which country's car is the Lynk & Co 03?

The Lynk & Co 03 is a Chinese car. The Lynk & Co 03 belongs to the compact car category, with body dimensions of: length 4639mm, width 1840mm, height 1460mm, a wheelbase of 2730mm, front and rear track widths of 1597mm, a fuel tank capacity of 50 liters, a trunk capacity of 431 liters, and a curb weight of 1512kg. The Lynk & Co 03 features a MacPherson strut front suspension and a multi-link independent rear suspension. It is equipped with a 1.5T turbocharged engine, delivering a maximum horsepower of 156PS, a maximum power of 115kW, and a maximum torque of 245Nm, paired with a 6-speed manual transmission.

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What Causes the Humming Sound After Replacing Old Tires?

Brief Description of How to Replace Automotive Air Conditioning Refrigerant

How much over the speed limit is driving at 115 km/h in a 100 km/h zone?

How to Upgrade the Navigation System in a Car?

What is the recommended tire pressure for SUVs in winter?

Why is shifting from P to R gear so tight?

Which country's car is the Lynk & Co 03?

Where is the fastest and most accurate way to check vehicle violations?

What are some good brake fluid brands?

What is the Difference Between SL and SN Engine Oil?

Why does white smoke appear for a few seconds when starting the car and then disappear?