What Causes the Noise When Releasing the Brake?

What is the function of the evaporator in a car's air conditioning system?

The function of the car air conditioning evaporator is to evaporate the low-pressure refrigerant coming from the expansion valve, absorbing heat from the air inside the car, thereby achieving the purpose of cooling the interior. Here are some relevant details: 1. The evaporator is a heat exchanger. High-pressure liquid refrigerant enters the evaporator through the expansion valve. Due to the atomization effect of the expansion valve, the liquid refrigerant turns into a mist, which then changes into a gaseous state under low-pressure conditions. This transformation process absorbs heat, making the evaporator cold. When air passes through it, it becomes cool air, achieving the cooling effect. 2. Evaporators come in tube-fin, tube-belt, and laminated types. Currently, passenger cars in China mainly use all-aluminum laminated and tube-belt evaporators, while large buses primarily use copper tube-aluminum fin evaporators. Medium-sized buses use several types, with tube-belt evaporators being the most common. 3. The refrigerant channels in the air conditioning evaporator are formed by two aluminum plates stamped into complex shapes, layered together to create a sandwich structure. Between each pair of plates, corrugated heat dissipation strips are placed, and then the layers are stacked one by one. 4. The air conditioning evaporator is located inside the evaporator box, which is typically situated in the middle of the dashboard. It is connected by high-pressure and low-pressure pipes, and it's important to ensure the sealing rings are properly installed. The evaporator has a long service life and can generally be used until the car is scrapped.

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What does 0w40 mean for car engine oil?

Engine oil 0w40 refers to the grade and viscosity of the oil. 0W indicates that this oil can be used in winter, with a corresponding freezing point of -35 degrees Celsius; 40 represents that the kinematic viscosity standard of the oil at 100 degrees Celsius is between 12.5mm2/s and 16.3mm2/s. Here are some related details: 1. W is the abbreviation for winter. 0w means this oil can be used both in winter and summer. 0W-grade viscosity oil ensures low-temperature fluidity at winter temperatures as low as -35 degrees (the oil won't freeze), while 40 indicates that at summer engine temperatures as high as 150 degrees, it maintains appropriate viscosity (not becoming too thin), providing proper lubrication to all parts of the engine. The oil grade includes two parts: classification and viscosity specification. 2. Oil classification is represented by a combination of two letters. The "S" series represents oil for gasoline engines, with specifications generally ranging from SA to SN (in alphabetical order, but without SI). Each subsequent letter indicates better performance than the previous one, with more additives to protect the engine; the later the letter, the higher the quality grade. International brands often have oil grades above SF. The "C" series represents oil for diesel engines. If both "S" and "C" letters are present, it means the oil is suitable for both gasoline and diesel engines. 3. The oil grade usually indicates viscosity and quality. The viscosity of lubricating oil is often marked with SAE grades, where SAE stands for the "Society of Automotive Engineers." W stands for winter, and the smaller the number before it, the better the oil's low-temperature fluidity, indicating it can be used in lower environmental temperatures and provides better protection for the engine during cold starts. The number after the "W" (after the hyphen) indicates the oil's high-temperature resistance, with higher numbers meaning better protection at high temperatures.

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What is the normal tire pressure for the Geely Emgrand GL?

The standard tire pressure range for the Geely Emgrand GL is 2.4-2.5 bar. Due to seasonal factors, the tire pressure can be appropriately increased by 0.2 bar in winter and reduced by 0.1 bar in summer. This data is based on the international GBT2978-2008 standard requirements. The tire pressure monitoring system (TPMS) in the Emgrand GL is located on the dashboard. The TPMS does not display specific pressure or temperature values for each tire but only shows a TPMS warning symbol and a tire pressure anomaly warning symbol. These two symbols are located on the dashboard below the driver's position. Generally, a tire pressure exceeding 2.8 bar is considered too high, while a tire pressure below 2.0 bar is considered too low. Hazards of overinflated tires: Reduced tire friction and adhesion, affecting braking performance; causes steering wheel vibration and misalignment, reducing driving comfort; accelerates wear on the central tread of the tire, shortening its lifespan; increases vehicle vibration, indirectly affecting the lifespan of other components; overextends the tire cords, reducing elasticity and increasing the load on the vehicle during driving. Hazards of underinflated tires: Increased friction with the road surface, leading to higher fuel consumption; causes heavy steering and misalignment, compromising driving safety; increases movement in various parts of the tire, leading to excessive rolling and abnormal heat generation; weakens the cords and rubber, causing delamination or cord breakage and excessive friction with the rim, damaging the tire bead and causing abnormal wear; multiplies friction with the ground, rapidly increasing tire temperature, softening the tire, and drastically reducing its strength. High-speed driving may lead to tire blowouts. If the tire pressure monitoring indicator light turns on (a yellow symbol with an irregular circle, no stamp on top, four small spikes below, and an exclamation mark inside), it is generally due to one of the following three reasons: Abnormal tire pressure: Usually triggers an alarm when below 1.8 bar or above 3.0 bar. In this case, the tire needs to be checked and the pressure adjusted. Tire pressure monitoring not reset: After inflating the tires, if the tire pressure is not reset in time, the system will still record the previous data, causing the indicator light to turn on. Simply reset the tire pressure to resolve this issue. Damaged tire pressure sensor: The tire pressure sensor, installed inside the tire and connected to the inflation valve, monitors tire pressure. If the sensor is damaged due to impact while driving, the tire pressure warning light will turn on. In this case, the sensor must be replaced.

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What is the highway ETC system?

Highway ETC (Electronic Toll Collection) translates to electronic toll collection, which is a non-stop toll collection system. Highways are equipped with one or multiple ETC lanes. The ETC toll collection method: Through dedicated short-range microwave communication between the onboard RFID tag installed on the vehicle's windshield and the microwave antenna on the ETC lane at the toll station, the system connects with the bank for backend settlement processing via networking technology, thereby achieving the purpose of vehicles passing through bridge and road toll stations without stopping to pay tolls. Banks install this type of ETC express card with a post-payment system. ETC application conditions are as follows: Provide the original and photocopy of the vehicle owner's valid ID card and vehicle registration certificate. The photocopy of the driver's license must include the page with the most recent annual inspection seal. Credit card application form. This credit card is used to bind the ETC card. After obtaining the credit card, swipe it twice and use the POS receipt to collect the ETC onboard device for free at designated outlets. No fees are charged during this process. Must be between 18 and 60 years old. Must own a vehicle under personal name. Below are precautions for ETC installation: Do not obstruct the view. It is best to install it behind the rearview mirror: Many vehicle models have a steeply angled windshield, which reduces the driver's field of vision. If ETC installation does not consider this, it may increase the driver's blind spots. Install it on the right side behind the rearview mirror to avoid obstructing the view. Do not interfere with charging: The ETC electronic tag consumes power but generally does not require charging or battery replacement because it has a solar panel on the back for self-charging. Therefore, during installation, avoid the blackened areas on the windshield and positions that may block the solar panel. Once installed, do not remove it casually: The button in the middle of the adhesive is an anti-tamper rod connected to a switch. After installation, the windshield will press the anti-tamper rod in. If removed casually, the rod will pop out and trigger the switch, locking the electronic tag and rendering it unusable. You will then need to visit an ETC service point to unlock it. This is designed to prevent multiple vehicles from sharing one device. Precautions for using ETC: The ETC transaction sensing range is 8 meters. To prevent the ETC device of the vehicle ahead from malfunctioning, maintain a distance of over 10 meters to avoid automatic sensing and paying for the vehicle ahead. The ETC lane recognition speed is 20 km/h. Driving too fast may result in failure to read vehicle device information and failed toll deduction. When using a debit card to bind ETC, insufficient balance may also lead to failed toll deduction.

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What are the body dimensions of the Bora?

The length, width, and height dimensions of the Bora are 4523mm/1775mm/1467mm, which are official data. The length of the Bora refers to the distance between two vertical lines perpendicular to the vehicle's longitudinal symmetry plane and touching the outermost protruding parts at the front and rear of the car; the width refers to the distance between two planes parallel to the vehicle's longitudinal symmetry plane and touching the outermost rigid fixed protruding parts on both sides of the vehicle; the height refers to the distance between the highest point of the vehicle and the vehicle's supporting plane. The Bora is equipped with two types of engines: a naturally aspirated engine and a turbocharged engine. The naturally aspirated engine has a maximum power of 83kW and a maximum torque of 145 Nm, with a maximum power speed of 6000 rpm and a maximum torque speed of 3900 rpm. The turbocharged engine has a maximum power of 110kW and a maximum torque of 250 Nm, with a maximum power speed of 5000-6000 rpm and a maximum torque speed of 1750-3000 rpm. The naturally aspirated engine is paired with a 6-speed automatic manual transmission and a 5-speed manual transmission, while the turbocharged engine is paired with a 7-speed dry dual-clutch transmission. There are national regulations regarding vehicle dimensions. According to the national standard "GB1589-89," the total width of a vehicle does not include side mirrors, and the limitation on vehicle width is to provide sufficient lateral clearance for overtaking between adjacent lanes. In other words, the significance of vehicle width data in national standards is to ensure sufficient space during overtaking, preventing accidents or situations where road markings are narrower than the vehicle's width. Additionally, national regulations stipulate that the total width of a vehicle must not exceed 2.5m to meet the requirements of public road usage.

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What are the reasons that cause the ABS warning light to illuminate?

ABS light can illuminate in various states, with different causes and solutions for each state, as detailed below: State 1: ABS warning light stays on continuously (most common). Cause 1: The ABS wheel speed sensor's sensing area is covered by dirt, mud, or other contaminants, affecting the sensor's ability to detect the corresponding speed signal. This prevents the ABS control unit from determining the vehicle speed and the wheel slip rate, thus failing to issue appropriate commands to regulate braking. Solution: Clean the dirt from the wheel speed sensor and adjust the gap between the sensor and the signal ring to restore normal function. Cause 2: Poor signal transmission due to loose connections between system wiring or poor contact in the ABS relay, leading to system malfunction. Solution: Check the wiring connections and reconnect any loose parts. State 2: ABS warning light illuminates intermittently but turns off during acceleration. Cause: When multiple vehicle electrical devices are in use, the battery voltage drops below 10.5V. As the engine speed increases, the voltage rises, causing the ABS indicator light to turn off. This can also happen if the ABS system's power supply voltage is too low, such as due to poor terminal contact or grounding issues. Solution: Check the battery's specific gravity, inspect the charging system, and examine the power supply (e.g., voltage relay or poor power contact). State 3: ABS warning light stays on after engine start and only turns off when the engine is turned off (IGFF). Cause: Poor grounding contact in the ABS hydraulic valve body; poor electrical connection in the ABS hydraulic valve body wiring; ABS control unit malfunction. Solution: Loosen and then retighten the grounding screw on the hydraulic valve body, cleaning the contact surface if necessary. Check for enlarged gaps in the connectors. Replace the ABS or ABS/ASR control unit if needed. State 4: ABS warning light illuminates during high-speed driving. Cause: During high-speed driving, the ABS control unit detects a significant discrepancy between the rear and front wheel speed signals. This can also occur if the tire or wheel rim specifications are incorrect. Solution: Refer to the vehicle's tire and wheel rim specifications, as indicated on the label near the fuel tank cap. State 5: ABS warning light illuminates intermittently. Cause: Improper adjustment of the brake light switch; poor internal contact in the brake light. Solution: With the engine running, press the brake pedal and use a finger to push the brake switch linkage all the way down. Then release the brake pedal to complete the self-setting position. Replace the brake light switch if necessary. If the ABS warning light is on, it is recommended not to continue driving. An illuminated ABS light indicates a malfunction in the vehicle's anti-lock braking system. During emergency braking, if the wheels lock up, the vehicle may skid uncontrollably, making it difficult for the driver to slow down or adjust the vehicle's trajectory, posing significant safety risks.

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What Causes the Noise When Releasing the Brake?

What is the function of the evaporator in a car's air conditioning system?

What does 0w40 mean for car engine oil?

What is the normal tire pressure for the Geely Emgrand GL?

What is the highway ETC system?

What are the body dimensions of the Bora?

What are the reasons that cause the ABS warning light to illuminate?

What is the gear shifting operation for a manual transmission car?

How to Read the Odometer?

How to Replace the Battery in an Old Toyota Car Key?

What transmission does the Beijing X3 use?