What are the differences between the BMW M240i and M2?

What is the difference between 15w40 and 5w40 engine oil?

The difference between 5W-40 and 15W-40 engine oils lies in their low-temperature fluidity. 5W-40: The 5W can withstand external low temperatures down to -30°C. 15W-40: The 15W can withstand external low temperatures down to -20°C. Additional information: 1. Engine oil: Engine oil, also known as motor oil, is a lubricant used for the moving components in the engine crankcase. Engine oil also serves to cool and clean the engine. Engine oil consists of base oil and additives. The base oil is primarily refined mineral oil, synthetic oil, or a blend of refined mineral oil and synthetic oil. Additives include antioxidants, viscosity index improvers, pour point depressants, anti-corrosion and anti-rust agents, detergents and dispersants, friction modifiers, and anti-wear agents. 2. The meaning of "W": The "W" stands for winter, and the smaller the number before it, the better the oil's low-temperature fluidity, indicating a lower usable environmental temperature and better protection for the engine during cold starts. The number after the "W" (after the dash) is an indicator of the oil's high-temperature resistance, with higher values indicating better protection at high temperatures.

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What causes car shaking when releasing the accelerator pedal?

Shaking when releasing the accelerator pedal may occur due to insufficient RPM during gear shifting, which is a driving technique issue that can be resolved by the driver. It could also indicate problems with the engine mounts, where engine RPM and vehicle speed resonate at the same frequency. Below are relevant explanations: 1. Causes of shaking: Another possible reason is severe uneven wear on the four tires. Avoid mixing spare tires for high-speed driving - spare tires should only be used temporarily and replaced immediately afterward. You can also check wheel balance and four-wheel alignment, as long-term misalignment may lead to uneven wear. Even with balanced braking force distribution across all four wheels, significant differences in braking effectiveness may still occur, causing shaking. This is usually not noticeable at low speeds but becomes apparent during high-speed braking when greater braking force is required. 2. Solutions: 1) Engine shaking in neutral while stationary; replace engine mounts. 2) Steering wheel shaking when braking at high speeds; replace front brake discs. 3) Body shaking during low-speed rapid acceleration; replace spark plugs. 4) Body shaking when pressing the accelerator that disappears upon release; replace the drive shaft.

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Can a Typhoon Blow a Car Away?

A typhoon with wind force of 12 can blow a car away. Here are the basic principles of pure electric vehicles: 1. Working principle of electric vehicles: Battery—Current—Power regulator—Motor—Power transmission system—Driving the car. 2. Technical principle: Pure electric vehicles use motors instead of fuel engines, similar to automatic transmissions. Traditional internal combustion engines can limit the speed at which torque is efficiently generated to a narrow range, which is why traditional internal combustion engine cars require large and complex transmission mechanisms; during the operation of pure electric vehicles, no gear shifting device is needed, making them easy to operate. Compared with hybrid vehicles, pure electric vehicles use a single power source, and the electronic control system greatly reduces the internal mechanical transmission system of the car, also reducing energy loss and noise caused by friction of mechanical parts, saving space and weight inside the car.

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Tesla 1500km Supercharging Validity Period?

Tesla's 1500km supercharging validity period is six months. Below are the relevant introductions: Dry electrode and pre-lithiation: What Musk values are Maxwell's two globally unique technologies - dry electrode and pre-lithiation. First, let's talk about this "dry electrode" technology. Dry electrode can also be called dry process electrode technology. As the name suggests, "dry process" must correspond to "wet process". Currently, the electrode manufacturing technologies in the market are mainly "wet process", which makes this "dry process" stand out. First, let's explain what wet process electrode technology is. Wet process electrode technology is a process where the binder, active material, conductive agent, dispersant and solvent are pre-mixed into a slurry, then the slurry is coated onto the current collector and dried to remove the solvent, and finally rolled into an electrode. In simple terms, the wet process requires liquid mixing, then coating, and finally rolling - a method of electrode production. The dry process, on the other hand, does not require making slurry, but directly rolls the electrode materials.

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Why Does the Car Get Foggy on Rainy Days?

On rainy days, even during summer, a temperature difference develops between the inside and outside of the car. The outside temperature is lower, while the inside temperature is higher. Consequently, the temperature of the car windows also drops. When the humid air inside the car encounters the cold windows, it condenses into fog. Additionally, the air is more humid on rainy days, and when opening and closing the car doors, water from wet shoes can be brought inside, increasing the humidity in the car and making it more prone to fogging. Here’s a quick solution: Immediately turn on the car’s air conditioning, set the defrost function to maximum, and direct the cold air towards the windows. The fog will typically clear within three seconds.

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Can You Drive with 120 kPa Tire Pressure?

Tire pressure of 120 kPa is drivable, but the vehicle can only sustain it for 30-50 km. You should replace the tire or refill the air as soon as possible. Hazards of low tire pressure: Increased friction coefficient with the road surface, leading to higher fuel consumption; Causes heavy steering and easy deviation, which are factors detrimental to driving safety; Increases movement in various parts of the tire, causing abnormal heating due to excessive rolling; Reduces the function of the cord and rubber, leading to delamination or cord breakage and excessive friction between the tire and rim, resulting in damage to the bead area and abnormal wear; Multiplies the friction between the tire and the ground, causing a sharp rise in tire temperature, softening the tire, and drastically reducing its strength. High-speed driving may lead to a blowout; Increases tire body deformation, making the tire side prone to cracking, while generating flexing motion, leading to excessive heating, accelerating rubber aging, cord fatigue, and breakage, and increasing the tire's contact area, accelerating shoulder wear. Methods to address insufficient tire pressure: If no damage is visible, simply inflate to normal tire pressure and reset the tire pressure system; If the tire is found to be punctured during inspection, drive to a tire shop promptly for repair and then reinflate; If the tire pressure warning reappears after some time of inflation but there is no puncture, it may be due to air leakage caused by rim deformation. It is recommended to check the rim and replace it.

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What are the differences between the BMW M240i and M2?

What is the difference between 15w40 and 5w40 engine oil?

What causes car shaking when releasing the accelerator pedal?

Can a Typhoon Blow a Car Away?

Tesla 1500km Supercharging Validity Period?

Why Does the Car Get Foggy on Rainy Days?

Can You Drive with 120 kPa Tire Pressure?

Where is the OBD interface located in the Civic?

Does a car purchased in August 2016 need an annual inspection in 2021?

Which Country Does Subaru Belong To?

What is the Chinese equivalent of the Euro 6 emission standard?