What is the difference between 225 tires and 235 tires?

Why Can't the Car Start with the Key?

Car key failure to start can be due to a locked steering wheel, incorrect gear position, or vehicle malfunction. Below are detailed explanations for these causes: Locked Steering Wheel: A locked steering wheel is a normal anti-theft feature. This occurs when the steering wheel is turned after the engine is turned off, typically from the straight position to another direction. The car's computer interprets this as a potential theft attempt and automatically activates the anti-theft system. Incorrect Gear Position: For an automatic transmission car to start, the gear lever must be in the N (Neutral) or P (Park) position. This is a safety design by manufacturers. If the gear lever is not in N or P, the car may move upon ignition, posing a significant hazard. Vehicle Malfunction: Examples include engine failure, ignition system issues, relay damage, or a dead battery. If the car fails to start due to a dead battery, unusual sounds may occur during ignition, and the battery warning light or engine fault light on the dashboard will illuminate.

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Is it legal to modify car seats?

Modifying car seats is illegal as it falls under unauthorized vehicle modifications. Below is more information about car modifications: Legal modification scope: Modifications to body color (including interior), engine, fuel type, and chassis number are permitted. However, changes to the body, chassis, or engine are only allowed if they are irreparably damaged or have quality issues. Proof from a repair shop and documentation of the origin of the replacement engine, body, or chassis must be provided when applying for modifications. Illegal modification scope: Unauthorized vehicle modifications refer to alterations to the vehicle's appearance, power system, transmission system, or braking system that exceed the original design load capacity and functions, and are not permitted by national laws or manufacturer approval, including the replacement of key components. There are certain restrictions on car modifications, and random modifications may result in failure to pass annual inspections. Therefore, any car modifications must comply with relevant regulations.

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What Fuel Consumption is Considered Fuel-Efficient?

Depending on the engine displacement of different vehicle models, the fuel consumption considered fuel-efficient will also vary with the engine size. For example, for models with an engine displacement below 2.5 liters, a comprehensive fuel consumption of around 7L/100km is generally considered fuel-efficient. Additionally, whether a vehicle is fuel-efficient also depends on factors such as its weight and category. Some fuel-saving tips include: for manual transmission models, coasting in neutral as much as possible while ensuring safety; cleaning carbon deposits in the engine; maintaining engine speed between 2000-2500 RPM, as higher speeds can overload the engine; improving fuel quality to ensure complete combustion in the engine; and maintaining a consistent speed while driving to avoid sudden stops. The safest and most fuel-efficient driving method is maintaining a steady speed in a straight line. The most fuel-efficient speed for small-displacement vehicles is between 60 to 80 km/h, while for medium-displacement vehicles, it's 80 to 100 km/h. In congested streets, try to maintain a safe distance from the vehicle ahead, gently lift the accelerator, and reduce the frequency of braking to minimize fuel consumption.

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Can idling for 30 minutes fully charge the battery?

Idling for 30 minutes cannot fully charge the car battery. If the battery is relatively new and has sufficient charge, it still requires about an hour of idling to fully charge. During idling, the alternator cannot output its maximum voltage and current, resulting in slower charging speed. The battery is a crucial component in a vehicle, responsible for storing electrical energy. Without it, the car cannot operate normally. When the engine is not running, the battery powers all electrical devices and is responsible for starting the engine. During engine startup, the starter motor, ignition system, and fuel supply system all require electricity to function.

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What is the passing score for the Subject 4 exam?

Subject 4 requires a score of 90 to pass. The Subject 4 exam consists of 50 questions, primarily presented in the form of case studies, images, and animations. Each question is worth 2 points, with a perfect score of 100, and a passing score of 90. The exam duration is 45 minutes, and the question types include true/false questions, single-choice questions, and multiple-choice questions. During the exam, if a candidate answers 6 questions incorrectly, it means they have failed and need to retake the exam. The number of questions is relatively small. During the exam, pay attention to the questions and then select the answers. Subject 4 separates the knowledge related to safe and civilized driving requirements, safe driving skills under complex conditions, and emergency handling from the original "Subject 1" into a standalone "Safe and Civilized Driving Knowledge Test," which is conducted after the actual road driving test.

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What are the components of the valve train?

The valve train consists of a camshaft, tappet, pushrod, rocker arm, valve spring, valve, and valve guide. Its function is to open and close the intake and exhaust valves in a timely manner according to the working process and sequence of each cylinder of the diesel engine, ensuring the timely supply of sufficient fresh air and exhaust gas. When the piston is in the compression and expansion strokes, it ensures the sealing of the valves. There are two types of valve trains: overhead and side-mounted. Overhead diesel engines are widely used in small tractors. The overhead valve train includes a drive group composed of timing gears and camshafts, a valve transmission group composed of tappets, pushrods, rocker arms, and rocker arm shafts, and a valve group composed of valves, valve springs, guides, spring seats, and locking plates.

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What is the difference between 225 tires and 235 tires?

Why Can't the Car Start with the Key?

Is it legal to modify car seats?

What Fuel Consumption is Considered Fuel-Efficient?

Can idling for 30 minutes fully charge the battery?

What is the passing score for the Subject 4 exam?

What are the components of the valve train?

Why is the car air conditioning cooling slower?

Which Came First: Cars or Traffic Lights?

Is Crystal Coating Necessary for New Cars?

Are Joint Venture Vehicles Considered Domestic Cars?