What is the difference between the VV5 and VV7?

Why does the BMW 320i experience intermittent idling vibrations?

Here is the relevant introduction to BMW idling vibrations: 1. Poor combustion: Idling vibrations are mostly simply attributed to poor combustion, and the solution is straightforward. Since the fuel in the tank cannot guarantee long-term freedom from impurities, nor can it ensure the fuel lines remain clean—gas stations regularly clean their underground fuel tanks, let alone the fuel lines of household cars—impurities and moisture in the fuel lines can cause misfires, cylinder misfires, and vibrations when participating in combustion. You can use S-YOU-PRO fuel additive three times in the fuel tank, followed by running three tanks of fuel. 2. Dirty fuel lines: If the issue is indeed caused by dirty fuel lines, this phenomenon will disappear, and the engine will run smoothly. If it doesn't run smoothly, regular cleaning isn't wrong either. You can take this as a reference.

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Why is there a metal friction sound when the car is driving at low speed?

When the car is driving at low speed, the metal friction sound is caused by the friction between the brake pads and the brake disc. Here are some additional details: 1. Reasons for the metal friction sound at low speed: The gap between the disc brake pads and the disc is very small, sometimes even "zero gap". When the disc is unevenly worn or has sand or stones stuck to it, a "metal friction sound" can occur at low speeds. The braking system is a crucial part of the car, as it affects both the driving stability and safety. 2. Braking system: The main components of the braking system include the vacuum booster pump, master cylinder, wheel cylinder, brake pads, and brake disc. The vacuum booster pump provides assistance, making it easier for the driver to press the brake pedal when braking.

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How long after canceling the subject 2 appointment can I reschedule?

You can reschedule the subject 2 driving test 10 working days after canceling the appointment. Introduction to Subject 2: Subject 2, also known as the small road test, is part of the motor vehicle driver's license assessment and is the abbreviation for the field driving skill test subject. The C1/C2 test items include five mandatory tests: reversing into a garage, parallel parking, stopping and starting on a slope, turning at a right angle, and driving on a curve (commonly known as the S-curve). Basic Operations: Subject 2 requires students to master the basic driving operation essentials and have the basic ability to control the vehicle. They should be proficient in the basic methods of driving on the field and internal roads, have the ability to reasonably use vehicle control components and correctly control the spatial position of the vehicle, and be able to accurately control the vehicle's driving position, speed, and route.

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What are the new regulations for driver's license annual review at the age of 60?

Drivers aged 60-69 are not required to submit physical condition certificates, while those aged 70 and above must submit one annually. Annual review deadlines: Holders of B1 licenses should undergo annual review at the vehicle management office within 30 days before the end of each scoring cycle. If no points are recorded during the scoring cycle, the annual review for that year can be exempted, and so on until the driver's license expires. If less than 12 points are recorded during the scoring cycle, an annual review at the vehicle management office is required. Scoring cycle: B2 driver's license holders must undergo annual driver review, which should be completed within 30 days after the end of each scoring cycle at the issuing vehicle management office. However, if there are no accumulated point deduction records during the current scoring cycle, the review for that cycle can be exempted.

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What Are the Causes of Engine Idle Noise?

Here are the causes of engine idle noise: Piston Slap: Piston slap is a common source of abnormal noise. Due to poor lubrication conditions, excessive wear occurs between the piston and cylinder wall, causing the clearance tolerance between the piston and cylinder wall to exceed the normal range. During engine operation, the piston skirt impacts the cylinder wall, producing a crisp "clanking" sound. This is usually more noticeable during idle or low-speed operation. Timing Gear: After prolonged use, coupled with improper gear clearance adjustment and poor lubrication conditions, timing gears can experience excessive wear. In severe cases, the gear teeth may even become worn down, leading to loose meshing between gears. When the engine runs, this produces a "whirring, clattering" sound. Piston Pin Noise: Due to excessive wear of components, the clearance between the piston pin and connecting rod bushing becomes too large, the fit between the connecting rod bushing and small-end bearing becomes loose, and the clearance between the piston pin and piston pin bore becomes excessive. This causes the piston to wobble during movement, colliding with the cylinder wall and generating abnormal noise.

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Should I Drive with ECO Mode On Normally?

It is generally not recommended to drive with ECO mode enabled during normal driving, as ECO mode restricts the engine's power output, reduces the sensitivity of the accelerator pedal, and affects the vehicle's performance. How ECO Mode Works: ECO mode primarily analyzes and evaluates factors that influence fuel consumption during vehicle movement, such as automatic transmission gear position, engine speed, vehicle speed, braking, and transmission fluid temperature. The ECU control unit then calculates the optimal fuel quantity to supply the engine, effectively reducing fuel consumption compared to standard driving modes. In simpler terms, it controls the engine's RPM through appropriate gear selection to minimize unnecessary fuel consumption. Types of ECO Mode: Generally, ECO modes can be divided into passive ECO driving mode and active ECO driving mode. Passive ECO driving mode mainly serves as a reminder or guidance function. Active ECO driving mode usually has a dedicated button; once activated, it alters a series of driving-related settings, such as reducing throttle response (making the accelerator pedal less sensitive), adjusting the transmission shift logic for better fuel economy (earlier upshifts), and in some vehicles, even adjusting the air conditioning output.

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What is the difference between the VV5 and VV7?

Why does the BMW 320i experience intermittent idling vibrations?

Why is there a metal friction sound when the car is driving at low speed?

How long after canceling the subject 2 appointment can I reschedule?

What are the new regulations for driver's license annual review at the age of 60?

What Are the Causes of Engine Idle Noise?

Should I Drive with ECO Mode On Normally?

Does the Ford Escort have high fuel consumption?

Can You Take the Driving Test Part 2 Before Part 1?

What to Do When the Car Windows Fog Up?

How long does it take to upgrade from C1 to B2?