Is It Normal for the Engine to Shake at Idle Speed?

How to Check if a Used Car Has Been in an Accident?

Buying a used car and checking if it has been in an accident: 1. First, check the paint: Large areas of repainting will result in paint thickness outside the normal range, which can easily be detected with a paint thickness gauge. Cars that have been in accidents usually show signs on the anti-collision beams. 2. Inspect the engine compartment: If you notice screws that have been turned or unusual folds or dents, further inspection is needed. 3. Check the A, B, and C pillars: First, observe for obvious dents or bumps, then remove the door frame's rubber seal to see if the welding points are neat. Methods to determine if it's a new car are as follows: 1. Check the manufacturing date: The vehicle's manufacturing date should match the one on the certificate of conformity, which is usually hard to alter. If the manufacturing date is more than 15 days old, it's considered an old car. 2. Examine the brake discs: Most small passenger vehicles today have disc brakes (at least the front brakes). Checking the brake discs is a very reliable method. Generally, after driving more than 200 kilometers, the brake pads will leave noticeable marks on the brake discs. There is usually a 1-2 mm gap between the brake pads and the outer edge of the brake disc. After a certain distance, this will leave what is commonly referred to as a "ledge" (the "ledge" on a new car is very low).

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Can Vehicle License Plates Be Transferred When Selling a Car?

Selling vehicle license plates: They cannot be transferred. Below is a related introduction on how to identify fake license plates: 1. Observe the font of the license plate: Since the font of motor vehicle license plates follows a unified national standard, but they are not produced uniformly nationwide, the size and structure of the fonts may vary. However, each province has its own characteristics in motor vehicle license plate production. With careful observation, it is not difficult to distinguish. Genuine plates, i.e., standard license plates, feature uniquely designed fonts with intellectual property rights, offering a good visual experience. Counterfeit plates often have a background color that is too blue or yellow, with fonts that are either too thin or too thick, or abnormalities at the bends of the characters. 2. Observe the coloring of the license plate: Due to differences in the quality and composition of the paint used for the base plate of vehicle license plates, genuine and fake plates will differ. Genuine plates are colored on the front with imported paint through a roller, resulting in even coloring that only covers the raised parts. Fake plates are usually painted with a brush or pen, appearing uneven with visible brush strokes. Additionally, some recessed areas may also be colored, giving an overall impression of rough craftsmanship. 3. Observe the reflectivity of the license plate: Genuine plates do not reflect sunlight but reflect under direct light. Fake plates may appear shiny from certain angles under sunlight but remain dull under direct light, without any reflection.

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Should the Roewe RX5 Plus use 92 or 95 octane gasoline?

According to the official vehicle manual recommendation, the Roewe RX5 Plus should use 92 octane gasoline. In addition to checking the appropriate gasoline grade in the vehicle manual, the Roewe RX5 Plus can also find this information on the fuel tank cap, which will be clearly marked. Typically, 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 use 92 octane gasoline, those between 10.0-11.5 should use 95 octane gasoline, and if the compression ratio is higher, 98 octane gasoline should be selected. However, with the application of some new technologies nowadays, the gasoline grade cannot be solely determined by the compression ratio. High compression ratio engines can also be tuned to use lower octane gasoline. This is because, apart from 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 Roewe RX5 Plus occasionally uses the wrong gasoline grade, simply switch back to the correct grade after the current tank is used up. 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, but the increase in octane number will change the fuel's ignition point, leading to delayed combustion in the engine. This means both the engine's power output and thermal efficiency will decrease, resulting in poorer performance as experienced by the driver. For vehicles recommended to use higher octane gasoline, using lower octane gasoline can cause engine knocking. This is because the significantly lower octane number reduces the fuel's ignition point, 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 makes the engine run very unstably. If the knocking is imperceptible, it only increases noise without obvious damage to the engine. However, noticeable knocking indicates severe engine conditions, where the vibrations not only affect driving stability but also cause abnormal wear on the pistons and cylinders, potentially leading to cylinder scoring in severe cases.

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When does the 2019 expressway toll-free period start?

The 2019 Spring Festival expressway toll-free period starts at 00:00 on February 4 (New Year's Eve) and ends at 24:00 on February 10 (the sixth day of the lunar new year), lasting for 7 days. According to the "Implementation Plan for Exempting Toll Fees for Small Passenger Vehicles During Major Holidays" issued by the state, the expressway toll-free period applies to four national statutory holidays: Spring Festival, Qingming Festival, Labor Day, and National Day, as well as the consecutive holidays determined by the State Council for these statutory holidays in the current year. The toll-free period starts at 00:00 on the first day of the holiday and ends at 24:00 on the last day of the holiday. Relevant information about the holiday expressway toll-free policy is as follows: 1. Introduction: The holiday expressway toll-free policy refers to the policy of exempting toll fees for small passenger vehicles during major holidays. 2. Policy Impact: Affected by the macroeconomic situation, although the toll-free policy during major holidays only applies to small passenger vehicles with fewer than 7 seats, the decline in manufacturing economy has led to a significant drop in freight demand in some regions, resulting in a year-on-year decrease in toll revenue during the free period. A report by Guojin Securities estimates that this policy will impact the performance of listed companies by approximately 5% to 10%.

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What to Pay Attention to When Buying a New Energy Vehicle?

Key considerations when purchasing a new energy vehicle are as follows: 1. License Plate Application: After picking up the vehicle, handle matters such as invoices and insurance; have the vehicle's certificate of conformity inspected at the Industrial and Commercial Bureau; obtain a tax payment certificate (which can also serve as a tax exemption certificate) at the Vehicle Purchase Tax Collection Center; then proceed to the Vehicle Management Office with the purchase invoice, confirmation documents, and other relevant materials to complete vehicle inspection, license plate selection, and registration. 2. Charging Station Installation: The importance of charging stations is akin to a mobile phone's power bank, as their widespread distribution facilitates convenient charging for new energy vehicles. 3. Vehicle Model Selection: Currently, mainstream electric vehicles are mainly categorized into micro electric vehicles and compact electric sedans. Micro electric vehicles offer limited space, making them suitable for commuting but not ideal for family use—examples include the Zhidou D2, Zotye E200, and BenBen EV. Compact electric sedans are typically three-box cars, suitable for both family and business use—examples include the Emgrand EV300, BYD Qin EV300, BAIC New Energy EU400, and Eado EV. 4. Subsidies: In addition to national subsidies, local subsidies are often available. For instance, Beijing matches the national subsidy amount 1:1, meaning the city provides the same subsidy as the national government. Shanghai, on the other hand, offers a subsidy of 40,000 yuan per pure electric passenger vehicle and 30,000 yuan per plug-in hybrid passenger vehicle (including range-extended models) on top of the central government subsidy.

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Must the Seat Belt Be Replaced After Locking?

After the seat belt gets stuck, check the hinge or locking position of the seat belt to see if there is dust or foreign matter. In this case, you can clean the foreign matter yourself. If the seat belt is locked and cannot be released, it must be replaced immediately. If the internal retractor of the seat belt ages, causing the seat belt to become too loose and unable to tighten in time, the seat belt should be replaced immediately to prevent the occupants from sliding out due to the loose seat belt in an emergency, which may cause injuries. If the impact is too strong, the person may be directly thrown out. If the seat belt has been subjected to strong tensile loads during use, it should be replaced in time for safety reasons, even if it is not damaged, and should no longer be used. If the vehicle is involved in a collision that causes the airbags to deploy or explode, the seat belt must be replaced at the same time. This is because during a collision, the seat belt will firmly restrain the occupants in the seat to cooperate with the cushioning protection of the airbags, but it will also suffer a great impact. Therefore, after an accident, even if the seat belt is not damaged, its strength will be greatly weakened, and it is recommended to replace it with a new one immediately. Precautions for using seat belts: Check the condition of the seat belt: If damage or other problems are found, it should be replaced immediately. One person, one belt: The seat belt should be fastened across the hips and chest, spanning the pelvis and rib cage. It should be used by one person only and should not be shared by two people. Avoid pressing on hard or fragile objects: The seat belt should not press on hard or fragile items, such as mobile phones or glasses. Retract and store in time: When the seat is unoccupied, the seat belt should be retracted into the retractor, and the buckle should be placed in the storage position. Seat belt maintenance: Avoid pressing the seat belt on hard or fragile objects, such as glasses, pens, or keys in clothes; avoid rubbing the seat belt on sharp edges to prevent damage; do not tilt the seat back too much, otherwise, the seat belt may not extend or retract properly; when the seat is unoccupied, retract the seat belt into the retractor to prevent the buckle from hitting other objects during emergency braking and causing unnecessary trouble. If the seat belt is too dirty, it can be wiped with a towel soaked in soapy water. Remember not to use bleach or fuel for cleaning, as this may corrode the seat belt; also, do not scrub with a hard brush to avoid damaging the seat belt and affecting its service life. The correct method is to gently brush with a soft brush and then wipe dry with a dry towel. Foreign matter in the seat belt buckle. Sometimes, we may encounter difficulty inserting the seat belt into the buckle or pressing the button several times without response when trying to release the seat belt. In this case, check if there is any foreign matter inside and clean it in time.

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Is It Normal for the Engine to Shake at Idle Speed?

How to Check if a Used Car Has Been in an Accident?

Can Vehicle License Plates Be Transferred When Selling a Car?

Should the Roewe RX5 Plus use 92 or 95 octane gasoline?

When does the 2019 expressway toll-free period start?

What to Pay Attention to When Buying a New Energy Vehicle?

Must the Seat Belt Be Replaced After Locking?

What Does the Wrench Symbol Mean on a Car?

Do I Need to Bring Photos for Subject 4?

What Causes Insufficient Power When the Engine is Hot?

What are the differences between xenon lights, halogen lights, and LED lights?