What problems should be paid attention to in the process of automobile maintenance?

First, the car needs to add antifreeze in winter. In cold winter, cars need more protection. Not only should the engine oil be changed for it, but also the antifreeze in the engine water tank should be changed for it. If it is a long-lasting four-season universal model, it can be replaced once every two years, but the concentration and quantity should be checked. If not, replace the antifreeze, drain the water, idle for a few seconds to completely drain the old liquid, and then add new antifreeze. At the same time, don't forget to replace the gasoline filter to reduce the influence of impurities and moisture in gasoline on the oil circuit. It is easier to catch a car in winter and the price is not expensive. Second, the car needs to be inspected in winter. For cars in winter, it is necessary to check them carefully. At least the following steps are indispensable. Check that the oil level of engine oil should be within the normal range, neither too much nor below the minimum. It is also cheaper to check, clean and replace the filter element of the air cleaner, thus reducing the suction resistance of the engine, increasing the intake of mixed gas, reducing fuel consumption and improving power. Check and replace the spark plug. Ignition in winter is a big problem. If the temperature is low, the ignition energy is low. If you don't like cars, you'd better replace multipolar spark plugs, which are not too expensive, easy to ignite and have much higher energy. Check the free stroke of the clutch. After long-term use in summer, the free stroke of frequently stepping on the clutch should be adjusted to make it more accurate to use the clutch in winter. Check brake fluid and clutch fluid. Brake fluid must be kept within the normal range, which is very important for the safety of clutch fluid in winter driving. Adjust the tightness of the hand brake. In winter, the road surface is slippery, and the hand brake has more functions. Need to adjust the tightness, be sure to pull when parking to ensure that it does not slip. Check the transmission oil of the transmission system. Car owners with fine maintenance must check the lubrication of the gearbox when they have time. If it turns black and is no longer lubricated, it should be replaced. Check the travel system differential oil. This is the most easily overlooked part, which is generally not remembered, and it also contains more lubricating oil. Check the tire pressure. In winter, the friction coefficient of pavement is low, so the tire pressure should not be too high, but it should not be too low. Low external temperature, brittle tires and low tire pressure will seriously accelerate aging. The tires swap places with each other. Because the car has a certain camber angle, the middle of the road is high and the sides are low, and the internal and external wear of the tire is very different. In order to ensure safety and reduce wear and tear, tires should be replaced regularly. Check the battery charge and concentration. After winter, the days are short and the nights are long, so cars travel longer in the dark. The liquid level of the battery should be checked to keep it within the normal limit, so as to ensure sufficient storage of lighting power in winter darkness. Clean and check the fuse box. Clean, check and replace the fuse with potential problems in time, keep the fuse box clean, and avoid the failure caused by fuse problems when driving in dark winter. Check and replace glass water in winter. In the environment below zero degrees Celsius in winter, the antifreeze winter glass water should be replaced, or more simply, an appropriate proportion of alcohol can be added to the glass water to achieve the purpose of lowering the freezing point and freezing resistance. Check the rubber wiper blade. The temperature in winter is low, and the aging rubber wiper blade is stiff and can't be used. In order to ensure safety, it is best to replace it at this time. Check the front backup lights and bulbs. Checking and replacing the black bulb in advance can reduce the possibility of changing the bulb in winter. Third, the items to be prepared for car driving in winter may snow at any time in winter. Snow chains, heating supplies and some spare tools should be prepared in advance in the car. Snow chains are necessary, and the tightness of snow chains should be consistent and symmetrical. If it is a truck, the goods should be evenly loaded, and the tire loads on both sides are basically equal. 4. When using coolant in winter, unscrew the radiator cover above the radiator, inject the coolant into the radiator inlet, and install the radiator cover after filling it up. Some gasoline engine cooling systems are equipped with antifreeze compensation systems. The compensation system consists of an expansion barrel and an overflow pipe connected to the water inlet seat of the radiator. There is an overflow port communicating with the atmosphere above the expansion barrel, and the lowest liquid level of the expansion barrel is higher than that of the radiator. The system can make the radiator full of cooling liquid, thus giving full play to the maximum heat dissipation function of the radiator. When the engine temperature is normal or high, the antifreeze of the radiator expands, and the antifreeze and the hot air above it will flow into the expansion barrel from the radiator; When the engine temperature is low, the antifreeze in the radiator will shrink, and the antifreeze will flow into the radiator from the expansion barrel, so that the radiator will always be filled with antifreeze. When the normal working temperature of the engine is normal, the antifreeze level of the expansion barrel should be kept within the marked range of the lowest position and the highest position. When releasing antifreeze, turn on the water tap under the engine block and radiator. If there is warm air, adjust the temperature selector on the warm air to the full open position. To make the water flow faster, loosen the air valve above the thermostat. In order to completely drain the antifreeze, if you see that the antifreeze in the expansion bucket has not been drained, you can remove the hose connected to the overflow pipe of the radiator inlet seat and install it after draining. V. Prevention of car fire prevention difficulties in winter Every winter, especially in the extremely cold weather of MINUS ten degrees, some vehicles are always difficult to start in the morning. Although there are many reasons why it is difficult to start a cold car, the quality of the battery is the premise. If the battery is not good, every ignition is not smooth and needs to be checked. Especially in winter, keeping the battery fully charged will save the trouble of pushing in the morning. Generally known batteries can be divided into two types: anhydrous type and water adding type. The former judges the working state of the battery according to the color change of the detector attached to the battery, while the latter judges the working state according to the water quantity of the battery. Although anhydrous batteries are convenient, their service life is usually shorter than that of water-added batteries, and their performance will gradually deteriorate after normal use for about one year, and it will probably be normal after two years. Water-added batteries have the advantages of being cheap and durable, and most of them can be used for more than two years. However, if you forget to add supplementary liquid regularly, the service life will be shorter than that of waterless batteries, especially for vehicles whose engine room temperature is easy to rise. If you use a water battery, you need to check the liquid level frequently. There is also a water injection battery with less water loss. Like the anhydrous battery, it also has a color detector, and a protective cover is added to the water filling hole cover, which is easily confused with the anhydrous battery. This kind of battery basically needs to be filled with water regularly, but after long-term use, it will be found that the battery water must be replenished slightly at the beginning of use, and the water volume has been maintained at the normal upper limit, without the trouble of frequent water addition. This new generation battery has both the convenience of anhydrous battery and the durability of rechargeable battery, which is very popular with car owners. If you stop at a red light at night, the light will dim, and when you step on the accelerator to start, the light will obviously light up again, and the engine will start slowly and weakly, which means that the battery life will be exhausted and must be replaced. If you don't want to replace it, you can also add additives with the function of repairing the electrode plate to the battery and keep it for a period of time. However, the dosage of additives must meet the dosage requirements. The connector of the battery wire is easy to loosen, which will make the current unable to be output or input smoothly. In addition to affecting the working efficiency of the vehicle electrical system, it will also directly reduce the life of the battery. Be careful not to have rust on the joint. The white-green powder generated by oxidation is easy to gather at the joint, which affects the supply of current. Check the battery connector, paying special attention to the danger of leakage and short circuit between the positive and negative electrodes. Be careful when adding battery water, and don't let acidic electrolyte splash on your body or car body. After inspection, a layer of moisture-proof agent can be sprayed on the battery connector. Some fully discharged batteries can withstand three times of charging after adding water, but their effective life and maximum storage capacity will be significantly worse than ordinary batteries. When you get off the bus, be sure to look back to see if the lights are off. Try to avoid using models that consume a lot of electricity, so as not to let the battery life end prematurely. It should also be noted that the control computer in some cars needs to be reset after changing the battery. In extreme cold weather, if the battery feels uncomfortable, it can also be removed, taken to the house for insulation, and then installed when lighting in the morning. Although this is a bit troublesome, it can ensure the smooth start of the vehicle. 6. The word adhesion in winter driving sounds strange, but understanding it is very helpful for winter driving. Adhesion means the adhesion between the tire and the road surface. Adhesion is the product of vehicle weight and pavement adhesion coefficient. This is the whole car. For a wheel, the adhesion of the wheel should be: the vertical ground reaction force of the wheel multiplied by the road adhesion coefficient. The adhesion coefficient is a fixed value that does not change with people's will, and it is related to the speed of the car and the sliding degree of the wheel on the road (including sliding and sliding). The thrust generated by the driving wheel when the car is running, the braking force generated by the car when braking, and the lateral ground reaction force that the car can meet the steering requirements according to the predetermined trajectory when turning must be provided by adhesion. The adhesion coefficient of various pavements is different. Good and dry cement concrete or asphalt pavement has the largest adhesion coefficient, and its peak value can reach 0.9, followed by gravel road, dirt road, compacted snow road and icy road. The peak value of ice road is only 0. 1, and the wheel slip is only 0.07. It can be seen that due to the extremely small adhesion coefficient of the ice road, it is difficult to move forward, turn and brake on the ice road. In severe cases, sideslip (tail flick) or bump will occur. Therefore, on the snowy road in severe winter, the bus station and its vicinity should be paved with sand or cinder to improve the adhesion coefficient of the road surface and ensure the driving safety. It has adhesion along the longitudinal and transverse direction of the car. However, when the longitudinal adhesion is more applied to the driving wheel or the braking wheel, the lateral adhesion will decrease. Therefore, when the wheel is locked, the wheel will slip on the ground. At this time, the longitudinal adhesion has reached the limit, and the lateral adhesion is obviously reduced, so the car can't turn (the steering wheel has turned an angle, but the car is still driving in the original straight direction). In another case, if the wheels (front-wheel drive) that turn when driving slip, the car can't turn as scheduled. When braking, if all four wheels are locked, there is no lateral ground reaction force (provided by lateral adhesion) to resist lateral forces (such as lateral slope of the road, centrifugal force during steering, lateral wind, etc.). Moreover, the car can't keep driving in a straight line, and it is likely to slip or spin, and the car is out of control, which is prone to traffic accidents. Therefore, you need to be extra careful when driving on roads with extremely low adhesion coefficient. Seven. Measures to be taken to prevent the driving wheel from slipping on the ice and snow road When a car starts on the hard and smooth ice and snow road, it often encounters the phenomenon of serious slipping of the driving wheel, which leads to the failure of the car to start. At this time, you should shift to a higher gear, start from the middle gear, and control the throttle at the minimum opening to prevent the engine from stalling. Loosen the clutch pedal slowly and evenly, so that the driving wheel does not slip, thus starting forward slowly. If you can't start, you need to improve the adhesion of the car to the road. You can put grass, boards or branches on the road, or install snow chains. You can also dig the road out of the groove along the direction of the driving wheel to facilitate the car to start. Eight, the winter maintenance experience of automobile engine fuel system shows that about 50% of the failures of gasoline engines are caused by the fuel system, and 50% of the failures of the fuel system are caused by unclean fuel (mostly caused by water in the fuel). There is always some water in gasoline. Part of this water is produced in the process of refining, and the other part is caused by external factors. At room temperature, fuel oil can dissolve some water, but when the temperature decreases, the solubility of water decreases accordingly, and excess dissolved water will gather. Because the specific gravity of water is greater than that of oil, it will slowly separate out and stay at the bend of oil circuit or filter, resulting in discontinuous oil supply. When the temperature is lower than the freezing point of water, water will condense and freeze, which will block the oil circuit and make the engine unable to work. In addition, the moisture in gasoline will corrode and destroy the components of the fuel supply system. This phenomenon has appeared. The common method is just to pour hot water into the fuel tank and pipeline, and then start the car until the ice melts and the fuel returns to normal temperature. But this method is too time-consuming and laborious, and it may not be completely effective. Sometimes it is even necessary to remove the pipes to remove ice.