What is the working principle of EGR?

Should You Hand Over the Car Keys When Washing Your Car?

When washing your car at a car wash, it's best for the owner to keep the car keys themselves. The staff at car washes can be quite diverse, with many people coming and going. If the car keys were to get lost, it would indeed be quite troublesome. 1. Keep your keys with you: It's safer to hold onto your keys while at the car wash. Moreover, it's best not to hand over the car keys to others for safety reasons. A car wash typically takes about 20 minutes, during which both the interior and exterior of the car are cleaned. Whether you're familiar with the place or not, it's advisable not to give your car keys to the car wash staff. 2. Common practice: The usual approach is to remove the car key, open all four doors, and not wander too far away. Even during routine maintenance at a 4S shop, don't just hand over the keys to the service technician and walk away. Instead, engage in a conversation with the technician, ask about some basic car knowledge, and build a rapport. This way, they are more likely to service your car as if it were their own.

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How many points are deducted for stalling the car in Subject 2 exam?

Stalling the engine once due to improper operation will result in a 10-point deduction. Other common situations that lead to point deductions include: Vehicle crossing the line, failing to enter the reversing area, stopping midway, not following the prescribed route or sequence, or exceeding the time limit will result in a 100-point deduction. For slope parking: if the right side of the vehicle is more than 30cm from the roadside line after parking, 10 points will be deducted; if more than 50cm, 100 points will be deducted; crossing or touching the line will result in a 100-point deduction; if the front bumper is not aligned with the pole line and the deviation is within 50cm, 10 points will be deducted; if the deviation exceeds 50cm, 100 points will be deducted. Subject 2 has a full score of 100 points, with evaluation criteria set for failure, 20-point deduction, 10-point deduction, and 5-point deduction. The exam is passed under the following conditions: ① For large buses, tractors, city buses, medium buses, and large trucks, a score of 90 or above is required; ② For other vehicle types, a score of 80 or above is required.

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What Causes a Car to Start Immediately When Cold but Not When Hot?

The reasons why a car starts immediately when cold but not when hot are: 1. Carbon deposits: At high temperatures, carbon deposits have a strong adsorption effect on gasoline. If there are excessive carbon deposits on the intake valve, throttle valve, or piston, they can adsorb some fuel, leading to an overly lean air-fuel mixture and affecting startup. 2. Coolant temperature sensor: The coolant temperature sensor adjusts the fuel injection pulse width. If it malfunctions and fails to provide the correct temperature signal, it will affect the engine's fuel injection, causing an abnormal air-fuel ratio and making startup difficult. 3. Intake air temperature sensor: Similar to the coolant temperature sensor, the intake air temperature sensor also adjusts the fuel injection quantity. A higher intake air temperature sensor reading results in a richer mixture, while an open circuit or poor grounding can cause an overly lean mixture. Both overly rich and lean mixtures can make starting difficult. 4. Fuel quality issues: After a hot engine shutdown, the engine compartment remains at a high temperature. If the fuel is prone to evaporation, it can form high vapor pressure in the fuel rail. When this pressure exceeds the fuel system's pressure, it creates vapor lock, causing the fuel injector to spray overly lean fuel vapor, making starting difficult. 5. Fuel injector leakage: Due to the high temperature immediately after engine shutdown, leaking fuel can turn into vapor and enter the intake manifold. A hot start under these conditions can result in an overly rich mixture, making starting difficult.

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What does highway toll ETC mean?

Highway ETC (Electronic Toll Collection) translates to electronic toll collection, which is a non-stop toll collection system. On highways, there will be one or more ETC lanes. ETC toll collection method: Through dedicated short-range microwave communication between the vehicle-mounted RFID tag installed on the vehicle's windshield and the microwave antenna on the ETC lane at the toll station, combined with software networking technology and bank backend settlement processing, the purpose of vehicles passing through bridge and road toll stations without stopping to pay tolls is achieved. Banks install this type of ETC express card with a post-payment system. ETC application conditions are as follows: Provide the original and photocopy of the vehicle owner's valid ID card and vehicle registration certificate. The photocopy of the driver's license should include the page with the most recent annual inspection stamp. Postal credit card application form. This credit card is used to bind the ETC card. After obtaining the credit card, swipe it twice and bring the POS receipt to the designated postal outlet to receive and install the ETC vehicle-mounted device for free, with no additional charges. Applicants must be between 18 and 60 years old. Own a vehicle registered under personal name. Below are precautions for installing ETC: Do not obstruct the view. It is best to install it behind the rearview mirror: Many car models have a large rearward tilt angle of the windshield, which reduces the driver's field of vision. If this is not considered during ETC installation, it may increase the driver's blind spots. Install it on the right side behind the rearview mirror to avoid obstructing the view. Do not affect charging: The ETC electronic tag consumes power but generally does not require charging or battery replacement because it has a solar panel on the back for self-charging. Therefore, during installation, avoid the blackened areas on the windshield and positions that may block the solar panel. Once installed, do not remove it arbitrarily: The button in the middle of the adhesive is an anti-removal lever connected to a switch. After installation, the windshield will press the anti-removal lever in. If removed arbitrarily, the lever will pop out and trigger the switch, locking the electronic tag and rendering it unusable. You will need to visit an ETC service point to unlock it. This is designed to prevent multiple vehicles from sharing one device. Precautions for using ETC: The ETC transaction sensing range is 8 meters. To prevent the ETC device of the vehicle in front from malfunctioning, maintain a distance of more than 10 meters from the vehicle in front to avoid automatic sensing and paying for the vehicle ahead. The ETC lane recognition speed is 20 kilometers per hour. Driving too fast may result in failure to read the vehicle's device information, leading to toll deduction failure. When using a debit card to bind ETC, insufficient balance will also cause toll deduction failure.

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Do you need to watch the traffic light when making a U-turn at an intersection?

If the gap is marked with a dashed line, the U-turn is not affected by the traffic light and does not require crossing the crosswalk. You can make a direct U-turn as long as it does not interfere with other normally moving vehicles and ensures your own safety. If the gap is marked with a solid line, then the U-turn requires crossing the crosswalk and is affected by the traffic light. If you need to cross the crosswalk to make a U-turn, you must yield to pedestrians: When pedestrians are walking on the right side of the crosswalk and have not reached the centerline of the road, vehicles on the left side of the road should slow down and allow them to pass safely. When pedestrians are waiting outside the boundary line between the motorized and non-motorized lanes and have not entered the road, vehicles should slow down and allow them to pass safely. If pedestrians cross the boundary line between the motorized and non-motorized lanes, vehicles must stop; otherwise, it is a violation and subject to penalties. If pedestrians are waiting at the centerline of the road but have not entered the motorized lane, vehicles must stop; otherwise, it is a violation and subject to penalties. If pedestrians cross the centerline of the road and enter the motorized lane, vehicles must stop; otherwise, it is a violation and subject to penalties. If the road is divided by a green belt and pedestrians are waiting in the middle of the road, vehicles must slow down and allow them to pass safely. Cases where U-turns are allowed: If there is a U-turn sign at the intersection, you can make a U-turn. If there is a U-turn traffic light, follow its instructions. If there is no traffic light, make a U-turn only if it does not interfere with other vehicles or pedestrians. If there is no explicit prohibition of U-turns or left turns at the intersection, you can make a U-turn. 'No explicit prohibition' means there are no signs like 'No U-turn' or 'No Left Turn,' and the centerline is not solid. U-turns are also allowed on yellow grid lines. Yellow grid lines are no-parking zones at intersections prone to congestion, entrances of important facilities, etc. Stopping on these lines (even for traffic lights) is a violation. However, U-turns are allowed on yellow grid lines unless there is a center divider. If there is a U-turn traffic light, follow its instructions—only make a U-turn when the light is green. If 'No Left Turn' and 'U-turn Allowed' signs appear together, U-turns are allowed but left turns are prohibited. Note that 'No U-turn' is not the same as 'No Left Turn.' Things to note when making a U-turn at an intersection: Check the road markings. If they are solid lines, U-turns are prohibited under any circumstances. Continue driving to find a suitable spot. If there is a 'No Left Turn' sign, even if there is no 'No U-turn' sign, U-turns are not allowed at that intersection because U-turns require a left turn first. U-turns must be made from the innermost left-turn lane. If you are in the second left-turn lane, you cannot make a U-turn at that intersection. Always yield to oncoming traffic when making a U-turn. If you interfere with their movement, you will bear full responsibility for any accident. Near the intersection stop line, lanes usually have guiding arrows. The leftmost lane may not always have a left-turn arrow. If it has a straight arrow, U-turns are prohibited even if there are no explicit 'No U-turn' signs.

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What Causes Car Jerking at Low Speed but Normal at High Speed?

Car jerking at low speed but normal at high speed indicates a malfunction. Here are three possible causes: 1. Excessive carbon deposits in the throttle body, fuel injectors, or intake manifold: Many malfunctions are caused by carbon deposits, and some vehicles may experience jerking due to this issue. It is recommended to regularly clean carbon deposits. 2. Poor fuel quality: Incomplete combustion. 3. Faulty spark plugs or ignition coils: This can lead to misfiring. These issues require inspection and repair at a service center to prevent further safety hazards.

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What is the working principle of EGR?

Should You Hand Over the Car Keys When Washing Your Car?

How many points are deducted for stalling the car in Subject 2 exam?

What Causes a Car to Start Immediately When Cold but Not When Hot?

What does highway toll ETC mean?

Do you need to watch the traffic light when making a U-turn at an intersection?

What Causes Car Jerking at Low Speed but Normal at High Speed?

Should the accelerator and brake be operated with one foot or two feet?

Can a Three-Cylinder Engine Be Replaced with a Four-Cylinder Engine?

How to Remove Odors in a New Car?

How Long Can You Park on the Highway?