What are the reasons for the BMW 320e90 displaying tire pressure loss?

How to Calculate the Outer Diameter of a Tire?

The calculation formula for the outer diameter D of a tire is: D = rim diameter + tire width × aspect ratio × 2. A tire is a circular ring, so it has inner and outer diameters, with the outer diameter referring to the diameter of the circle in contact with the ground. The size data of the tire are marked on the sidewall of the tire, which includes recommended tire pressure, size, production date, speed rating, load index, and other information. Relevant information about car tires is as follows: 1. A tire is a circular elastic rubber product mounted on various vehicles or machinery that rolls on the ground. 2. Car tires are one of the important components of a vehicle. They directly contact the road surface and, together with the car suspension, help to absorb shocks during driving, ensuring good ride comfort and smoothness. They also ensure good adhesion between the wheels and the road surface, improve the vehicle's traction, braking, and off-road capability, and bear the weight of the car.

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How long can Honda keybatt last?

Honda keybatt can typically last for about one to two days, and it is recommended to replace it as soon as possible. Keybatt indicates that the remote key battery is low and needs to be replaced. Replacing the key battery: Gently press the small switch on the back of the key to remove the mechanical key. Then, use the mechanical key to open the key cover by inserting it into the notch next to the key and gently prying it open. Remove the key compartment cover to reveal the position of the old battery. It is recommended to use a small flat-head screwdriver for easier removal of the old battery. Ensure the new battery is placed with the positive side facing up, then reinstall the key cover and mechanical key. Confirm that the key functions properly. Precautions for battery replacement: Do not use the wrong battery. The battery life of a smart car key is approximately one year. Battery consumption varies depending on the frequency of key usage. Different distances when using the key will also affect power consumption. Be very cautious when replacing the battery for a smart car key, as any mistake can damage the circuit board inside the key.

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How to Check a Car Air Conditioning Compressor?

Car air conditioning compressor inspection methods are as follows: 1. Compressor sealing check: Since the refrigerant has strong permeability, the sealing of the compressor greatly affects the air conditioning system. The method to check compressor sealing is: Use a manifold gauge to detect, connect the high and low-pressure hoses of the manifold gauge to the high and low-pressure service valves of the compressor respectively, start the engine to run at idle speed at 2000r/min. When the compressor is working normally, you can hear the metal sound of the internal piston movement. The normal working low-pressure display value is 0.15~0.20MPa, and the high-pressure display value is 1.42~1.47MPa. 2. Measurement of the resistance value of the compressor electromagnetic clutch: First remove the electromagnetic clutch coil from the compressor, then measure its resistance with a multimeter. Since the standard resistance of the electromagnetic clutch coil is (3.7±0.2)Ω, use the ohmmeter range of the multimeter to avoid measurement errors. If the multimeter pointer does not move during measurement, it indicates that the electromagnetic clutch coil is open. If the measured value is less than 3.5Ω, it indicates that the coil is short-circuited, open, or the electromagnetic coil should be replaced. 3. Compressor operation status check: (1) Whether the drive belt is broken or loose. If the drive belt is too loose, it will slip, accelerate wear, and fail to transmit power. (2) Whether there is noise inside the compressor. (3) Whether the compressor clutch is slipping.

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Why is there abnormal noise when starting the car and braking?

The reasons for abnormal noise when braking during car startup are as follows: 1. It may be due to the sound caused by friction between the brake pads and brake discs, which is related to the material of the brake pads. If the brake pads are too hard or contain excessive impurities, they can be removed and polished to ensure a smooth contact surface, restoring normal function, reducing wear on the brake discs, and ensuring stable, comfortable, and safe driving through timely maintenance. 2. If it is a new car or newly replaced brake pads, the new brake pads and brake discs require a break-in period. When braking, this abnormal noise may occur, which is completely normal. Additional information: Brake pads are consumable items with a certain thickness. Manufacturers intentionally add some metal particles when the brake pads are close to their wear limit. When the wear reaches a certain level, braking will produce a different noise than usual to remind the owner that the brake pads need replacement.

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How to Drive a Manual Transmission Car More Fuel-Efficiently?

Here are some methods to drive a manual transmission car more fuel-efficiently: 1. Control RPM: For most small cars, the optimal engine RPM range is between 1500 and 2500. Maintain this range in any gear. Excessive RPM increases unnecessary fuel consumption and harms the engine, while too low RPM causes lugging and also damages the engine. 2. Control shifting RPM: When shifting gears, slightly increase the throttle to raise the RPM to just above 2500. Otherwise, the speed will drop after shifting, requiring additional throttle to compensate, which consumes more fuel. 3. Maintain optimal speed: The most fuel-efficient driving state is maintaining an appropriate speed. For example, the best speed for small-displacement cars is 80 km/h, while for medium-displacement cars, it's 100 km/h. Different gears have different optimal speeds. 4. Avoid frequent lane changes, overtaking, and braking: Try to maintain a steady speed, keeping the engine within the optimal RPM range. Constant overtaking, lane changes, and sudden braking not only waste fuel but also wear out the car and increase the risk of accidents. If you need to stop ahead, ease off the throttle early and coast in gear to slow down, rather than braking abruptly at the last moment. 5. Lighten the trunk: The heavier the vehicle, the higher the fuel consumption. Avoid overloading the trunk and remove unnecessary items that are not needed for long periods.

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Where is the intercooler generally located?

Automotive intercoolers are located behind the front bumper of the vehicle, near the radiator. Intercoolers are typically only found on vehicles equipped with superchargers or turbochargers, as they are actually supporting components for turbocharging systems. Their function is to reduce the temperature of high-pressure hot air after compression, thereby decreasing engine thermal load, increasing air intake volume, and consequently enhancing engine power. Below is relevant information: 1. For supercharged engines, the intercooler is a crucial component of the forced induction system. Both mechanically supercharged and turbocharged engines require an intercooler installed between the compressor and the intake manifold. 2. If uncooled compressed air enters the combustion chamber, it will not only affect the engine's volumetric efficiency but also easily lead to excessively high combustion temperatures, causing issues such as engine knocking. Additionally, it will increase NOx emissions in engine exhaust, contributing to air pollution. To address the adverse effects caused by temperature rise in compressed air, an intercooler is necessary to lower intake air temperature.

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What are the reasons for the BMW 320e90 displaying tire pressure loss?

How to Calculate the Outer Diameter of a Tire?

How long can Honda keybatt last?

How to Check a Car Air Conditioning Compressor?

Why is there abnormal noise when starting the car and braking?

How to Drive a Manual Transmission Car More Fuel-Efficiently?

Where is the intercooler generally located?

What is the fuel consumption of the Buick Regal?

What does AT mean on a car?

Which Gear is More Fuel-Efficient on the Highway, D or M?

What does the AUTO button on a Mercedes-Benz mean?