What to Do If 12 Points Are Deducted During the Probationary Period?

What are the symptoms of a faulty expansion tank cap?

Here are the symptoms of a faulty expansion tank cap: 1. After the expansion tank cap is damaged, coolant will spray out from the radiator cap. 2. When the tank cap is damaged, the flow of coolant entering the engine will decrease, leading to a drop in coolant pressure. The heat generated during engine operation cannot be dissipated, which may cause the engine to overheat. In severe cases, boiling over may occur. Below is some relevant information: 1. Most automotive engine cooling systems use an automatic compensation closed-type radiator, primarily equipped with a reservoir. The reservoir cap has a steam valve and an air valve. The advantage of this design is that it reduces coolant loss in the cooling system while improving the radiator's heat dissipation performance. 2. When the pressure in the cooling system exceeds the steam valve's pressure, the steam valve opens, and the radiator starts working. This helps lower the temperature around the engine, ensuring it operates within the normal temperature range. 3. When the engine is running, the coolant continuously circulates in the cooling passages. If the internal pressure is too high, the coolant may leak out, potentially causing pipe bursts. 4. The coolant reservoir has maximum and minimum level marks. When adding coolant, ensure it is filled between these two marks.

5

Share

What to Do When the Right Car Door Scrapes Against a Wall?

Drivers need to maintain high concentration while operating a vehicle. Below are relevant solutions for when the right car door scrapes against a wall: 1. Minor damage: It is recommended to leave it as is. Daily usage inevitably leads to some hard objects scratching the car paint, such as zippers on pedestrians' backpacks or small stones kicked up during driving, leaving slight marks on the paint. This does not affect the overall appearance of the vehicle. 2. Light damage: A touch-up pen can be used. In such cases, the scratches on the paint surface or marks left by friction with objects are usually very visible. For this type of damage, I and many repair technicians would recommend using a touch-up pen for treatment. 3. Moderate damage: Take it to a repair shop. If the car paint is damaged to the extent that the primer is exposed, it must be addressed promptly to prevent the affected metal panel from rusting due to rain or other factors. 4. Severe damage: Send it directly to an authorized service center. After the original factory painting process, the paint needs to be baked at temperatures above 200°C. Only professional paint repair shops or authorized service centers can ensure that the repaired paint closely matches the original paint to the greatest extent.

6

2

Share

Is a Bulging Tire a Quality Issue?

Not necessarily. There are many reasons for tire bulging, and it is not always caused by tire quality issues. Poor driving habits can also lead to tire bulging, so it is important to regularly inspect the tires during daily driving. Here are the factors that can cause tire bulging: 1. Low aspect ratio: A low aspect ratio means the tire sidewall is thin. Such tires have strong grip and a sporty feel, enhancing vehicle handling. However, the sidewall cushioning area is small, making it prone to cuts from the rim during impacts, which can lead to bulging. 2. Abnormal tire pressure: When tire pressure is too high, the tire becomes stiff, and the cord layers can easily break upon hitting hard objects. When tire pressure is too low, the tire flattens, and the rim can shear the sidewall, also causing cord layer breaks. 3. Impact with hard objects: During driving, if the tire collides with a hard object, the strong impact can cause severe compression, increasing internal air pressure and leading to bulging on the thinner side. 4. Expired warranty: Tires have a warranty period, typically 3-5 years. After expiration, bulging is more likely to occur during use.

13

2

Share

Should the A4L use 92 or 95 octane gasoline?

According to the official vehicle manual recommendation, the A4L should use 95 octane gasoline. In addition to checking the appropriate gasoline grade in the vehicle manual, the A4L can also check it on the fuel tank cap, which will also be marked. Usually, the gasoline grade can also be determined based on the engine's compression ratio. Vehicles with an engine compression ratio between 8.6-9.9 should choose 92 octane gasoline, while those with a compression ratio between 10.0-11.5 should choose 95 octane gasoline. However, with the use of some new technologies, the gasoline grade cannot be determined solely by the compression ratio. A high compression ratio can also be tuned to use lower octane gasoline. This is because, in addition to the compression ratio, other factors such as ignition timing, turbocharging technology, and Atkinson cycle technology also play a role. Generally speaking, the higher the gasoline grade, the higher the octane number and the better the anti-knock performance. 92 octane gasoline contains 92% isooctane and 8% n-heptane, while 95 octane gasoline contains 95% isooctane and 5% n-heptane. If the A4L occasionally uses the wrong gasoline grade, simply switch back to the correct grade after use. However, long-term use of the wrong gasoline grade can have the following effects: For vehicles recommended to use lower octane gasoline, using higher octane gasoline will not cause damage. However, the increase in octane number will change the fuel's ignition point, leading to delayed combustion in the engine. This means the engine's power output and thermal efficiency will decrease, resulting in poorer performance. For vehicles recommended to use higher octane gasoline, using lower octane gasoline can cause engine knocking. Because the octane number is too low, the gasoline's ignition point decreases, causing it to ignite prematurely during the compression stroke. If the fuel ignites before the spark plug fires during the compression stroke, resistance will occur during the upward stroke. This resistance will make the engine run very unstable. If the knocking is mild, it will only increase noise without significant damage to the engine. However, if the knocking is severe, it indicates that the engine's condition is very serious. The vibration not only affects driving stability but can also cause abnormal wear on the piston and cylinder, and in severe cases, even cylinder scuffing.

1

0

Share

What are the symptoms of a damaged lower control arm ball joint?

The symptoms of a damaged lower control arm ball joint include steering wheel vibration at higher speeds, knocking noises when driving on bumpy roads, and a clunking sound transmitted through the steering wheel on uneven surfaces. Below are detailed explanations about lower control arm ball joint damage: 1. To diagnose lower control arm ball joint failure, lift the vehicle using a jack or lift, then repeatedly shake the wheel left-right and up-down multiple times to check for play and determine whether it's the steering linkage ball joint or upper/lower control arm ball joint that's damaged. 2. Hold the tie rod or drag link and shake it left-right - if there's noticeable movement, immediate replacement is needed to prevent loss of steering control. Check wheel play horizontally to identify whether it's the steering gear or CV joint, and vertically to determine if it's the lower control arm or CV joint. 3. Loud clicking noises during sharp turns on both smooth and rough roads typically indicate CV joint failure, while metallic clanging sounds from the chassis on bumpy roads usually point to stabilizer bar damage. The exact severity of wear can be determined by observing the ball joint's movement range. 4. Severe ball joint wear will cause noticeable wheel wobble, vibration, or instability at low speeds, accompanied by stiff steering. Visible signs include torn rubber boots, grease leakage, and impaired steering response. For passenger vehicles, lower control arm ball joint damage directly impacts both ride comfort and safety.

5

2

Share

What is the fuel consumption of the Luxgen U5?

The fuel consumption of the Luxgen U5 is 6.3-6.5 liters per kilometer. Additional information: Methods to reduce fuel consumption are as follows: 1. Regular maintenance: Regular maintenance can reduce the failure rate of the car and also lower fuel consumption. Maintenance includes periodic replacement of parts such as spark plugs, oil filters, brake fluid, radiator coolant, air filters, power steering fluid, transmission fluid, etc. Keeping the vehicle in optimal condition helps reduce fuel consumption. 2. Avoid hard acceleration: Hard acceleration only shortens driving time by 4%, but increases fuel consumption by 37%-40%. On typical city roads, the speed should be maintained at around 50 km/h, with engine RPM generally between 2000-2500. On highways, the speed should be between 90-110 km/h. For every 10 km/h increase in speed, fuel consumption increases by 10%. Avoid hard acceleration as RPM is the biggest factor affecting fuel consumption. 3. Reduce weight: For every 100 kg increase in vehicle weight, fuel consumption increases by 4%-5%. 4. Maintain normal tire pressure: Checking tire pressure not only benefits fuel consumption but also ensures driving safety. Develop a habit of checking tire pressure daily. Generally, the front tire pressure should be 2.2-2.3, and the rear tire pressure should be 2.4-2.5.

19

2

Share

What to Do If 12 Points Are Deducted During the Probationary Period?

What are the symptoms of a faulty expansion tank cap?

What to Do When the Right Car Door Scrapes Against a Wall?

Is a Bulging Tire a Quality Issue?

Should the A4L use 92 or 95 octane gasoline?

What are the symptoms of a damaged lower control arm ball joint?

What is the fuel consumption of the Luxgen U5?

How to Determine if an Oxygen Sensor is Good or Bad?

Which is Better: External or Internal Tire Pressure Monitoring?

Where is the cabin air filter installed?

How Many Years Do Snow Tires Generally Last?