Mr. rider Liao asked: Recently, his car has some difficulties in cold start, and after the fire, the exhaust pipe will be black smoke. What is the matter? Answer: cold start is a bit difficult. After starting up, the exhaust pipe will take black smoke to do computer test first. Check the working condition of oxygen sensor and water temperature sensor. Because the starting difficulty is to distinguish from which system is caused by the following system, you can focus on checking the startup system (battery, boot machine, ignition switch), oil supply system (gasoline pump, oil pressure, injection nozzle), ignition system (spark plug, cylinder line, ignition coil), engine system (cylinder pressure, oxygen sensor, etc.). Mr. Che Youlei asked: his car has been open for more than four years. In the near future, it is easy to extinguish when the speed of the car is less than 30 kilometers per hour. What is this? Reply: as you have described, it may be that the air fuel ratio is too high. You can adjust it to 4S shop or repair shop. Because the air fuel ratio is high, the oil burns slowly and the power is not enough, so we need to step on the accelerator quickly. In this case, the air-fuel ratio is generally adjusted. Mr. Suu Shu asked: Recently, when I was driving, I found that the oil lamp was calling the police after the car was out of action. How do I do this? Response: the cause of the oil lamp light is mostly caused by the low oil pressure in the engine oil channel. In addition, there is a possibility that the oil induction plug and its connection line have problems. Therefore, it is suggested that first test the oil pressure is too low. The main cause of low oil pressure is the following reasons, one is the poor working performance of the oil pump or the low oil pressure caused by the existence of abnormal wear; two is the abnormal operation of the oil limiting valve; three is the excessive wear of the related bearing bush, which leads to the excessive clearance, and then the oil pump enters the oil. The phenomenon of blockage in the mouth or collector leads to insufficient oil supply and low oil pressure. Therefore, it is suggested to drive to the specialized shop for the inspection of the vehicle on site test. Miss Li asked: Recently, when the handbrake was released and ready to drive, the hand brake lamp on the dashboard was still on. What's the matter? Reply: according to the condition of failure and the control principle of automobile hand brake light, if the liquid level of the brake fluid is normal, it is suggested that the handbrake switch and the brake oil cup liquid level sensor be inspected in the repair shop. If the hand brake switch is not in contact with the liquid level sensor, it will directly cause the above reasons. The barrier occurs, otherwise it will be repaired or replaced. Mr. Liu asked: Recently, when driving, it was found that the car screen often jumped out of the direction of the headlights. Answer: in such a situation, the main problem is to make a free replacement at the 4S store on the headlamp sensor. In the field of automotive lighting, the servo steering headlights are regarded as more sophisticated technical equipment. The general lamp installed on the car has a fixed illuminating range. When the car turns on the bend at night, the blind area often appears on the inside of the bend, which greatly threatens the driver's safe driving at night. It can automatically adjust the deflection of the headlight according to the driving speed and steering angle so that it can illuminate the "not" area in advance and provide all directions of safety lighting to ensure that the driver has the best visibility at any time.