[Summary] Summer is hot and rainy, is a multi-issue car failure, many of the common faults in the summer traffic carefully observed, we find it easy to find some objective laws, so that our car can better serve us . The main parts of the summer car often fail include: cooling system, air conditioning system, fuel supply system, internal engine failure. Key words inspection and maintenance First, the cooling system Summer, the most common car cooling system fault is the "tank boil," the car broke down, a loss of water. Along with the water tank boiling and loss of water, there is acceleration and other failures. First of all, make sure that other related parts of the vehicle are normal, such as using the fuel, engine oil, spark plug, anti-freeze fluid, ignition timing and idle air-fuel ratio correctly. Further inspection of the cooling system should all be normal. Check the order should be: first look at the water tank. The normal temperature of the water tank should be the same when driving the car, if there is half the heat of the cold side of the situation, you can determine the internal blockage of the tank. Can be connected to the water tank 2 kg pressure pipe, reverse flushing, if the blockage can use a small amount of cleaning agent, pay attention to cleaning the tank dirt and observe whether there is leakage. Second look at the thermostat. Some people think that removing the thermostat can prevent the water temperature is too high, in fact, as long as the normal functioning of the thermostat does not cause the water temperature is too high, and the engine running at low temperatures for a long time is also very harmful; In addition to many engine thermostat Is a two-way effect, when the thermostat is closed, forcing the cooling water to go small cycles, and the thermostat is turned on, the small cycle off, all the cooling water to go big cycle. If not installed thermostat, due to the pipeline local resistance throttling effect, the actual flow to the big cycle is very little water, water temperature but increased. Finally check the pump. Pump damage in three ways: leakage, lost rotation and impeller corrosion. The so-called lost turn is the pump shaft and impeller with the gap is too large, when the engine speed reaches a certain, the pump impeller can not reach the appropriate speed, resulting in poor water circulation. Fans are the main components of the cooling system. Some cars have eliminated fixed fans and replaced them with electromagnets and fans with silicone clutches. It is characterized by the basic function of the car when the cold car does not work, while the heat when the car reached the maximum heat; silicone oil fan clutch is the main fault oil leakage, electromagnetic fan clutch is the main fault water temperature switch damage, line damage, electromagnetic coil damage . Engine cooling in addition to water as the cooling medium, some heat can also be lost with the exhaust, the oil can also take away some of the heat, and the air around the engine play an irreplaceable role more, so check the engine overheating do not forget to check Exhaust system (especially with catalytic converter models) is smooth, oil, transmission oil cooling device is intact. In addition, the wind guide cover (commonly known as air ring) near the engine fan plays a vital role in the thermal convection in the cabin, and attention should be paid when checking. In order to prevent the cooling system from malfunctioning, pay attention to the maintenance of the cooling system. The maintenance of the cooling system includes: 1. Check the sealing condition of the cooling system, the tightness of the fan belt, the sensitivity of the thermostat and the cooling water temperature etc., Cooling water. 2. Wash the cooling system, including the radiator, water scale adhesion within the scale, to prevent the scale of the cooling system cooling performance. Second, the air-conditioning system: summer air-conditioning systems often appear poor cooling failure phenomenon, in order to ensure the normal operation of the car air-conditioning system, to be properly used, routine maintenance, regular maintenance, but also on the air-conditioning system for routine inspection. Check the methods are the following: 1, the hand touch the surface temperature of the cooling pipe feel, when touched by hand to the refrigerant pipe, the low pressure pipe temperature is lower, the high pressure pipe temperature is higher. High pressure line: From the compressor outlet → condenser → reservoir → expansion valve inlet. Low pressure line: outlet from expansion valve → evaporator → compressor inlet. There should be a significant temperature difference on the compressor side. 2, with the eye observation refrigeration system leakage site, all the connections in the refrigeration system or condenser surface once found grease, indicating there is a refrigerant leak. Can also be used thicker soapy water smear in the suspicious place to observe whether there is a bubble. 3, from the installation of the tank at the top of the observation port to determine the condition (1) clear, no bubbles. If the air outlet is cold, indicating that the cooling system is working properly; if the air outlet is not cold, indicating a serious refrigerant leakage; if the outlet air-conditioning inadequate, turn off the compressor 1min after the bubble still flowing slowly, or stop the compressor The moment is clear and no bubbles, indicating too much refrigerant. (2) occasional bubbles. If the expansion valve frosted, then there is moisture; if the expansion valve is not frosted, it may be lack of refrigerant or air. (3) oil window on the observation window, the outlet is not cold, then there is no refrigerant in the refrigeration system. (4) bubbles appear very turbid, refrigeration system may be added too much frozen oil. In summer, in addition to the above air-conditioning system inspection, should also pay attention to the following points: 1. Whether the refrigerant enough. This is a common cause of air conditioning not cooling. Adequacy of refrigerant can be seen through the observation holes on the drying canister, an experienced repairman can determine from the air bubble flow whether the air conditioner needs to be replenished. If you find that the lack of air-conditioning refrigerant first do not rush to replenishment, you should first check whether there is a refrigerant leak, according to experience, air-conditioning system failure more than 80% is due to refrigerant leakage caused. 2. Check the air conditioning system pressure is appropriate. After confirming the refrigerant is not a problem, you can check the system pressure is normal, in general, the normal low-pressure air-conditioning system of the pressure 0.15-0.2MPa, high-pressure end of the pressure of 1.35-1.55MPa, depending on the car. If there is not much difference between high and low pressure, then it is likely that the compressor is not working well or does not work at all. The normal air conditioner compressor should be able to easily rotate by hand, if the tools are not moving, you can determine the compressor lock, you must replace. 3. Drying tank or expansion valve is normal. If the inspection reveals that the pressure at the high pressure end is particularly high and the pressure at the low pressure end is particularly low, it is likely that the dry canister or expansion valve has failed. In practice, dry cans and expansion valves should be considered as delicate materials or "consumables "They must be replaced on a regular basis, especially for those vehicles that have been in operation for five years. 4. Electronic control system is reliable. In order to make the work of air conditioning stable, comfortable and save fuel, many high-end cars equipped with sophisticated air-conditioning electronic control system, if these problems can cause air-conditioning abnormalities. Third, the oil supply system Summer gas supply system is prone to air resistance phenomenon. This is due to the oil system is heated, part of the light gas in gasoline volatilized into a gas, there and the gasoline pipeline and gasoline pump, increased resistance to flow of gasoline; combined with high summer temperatures, likely to cause insufficient or even interrupted generator oil supply phenomenon. There are several ways to prevent the phenomenon of air resistance: 1. The phenomenon of air resistance occurs on the way, can be wet cloth to make the gasoline pump cool or open the vehicle to the cool place to make the gas resistance phenomenon can be excluded. 2. Change the installation position of the diaphragm pump from the original close to the rear of the exhaust pipe to the exhaust pipe in front of a well-ventilated place and between the gasoline pump and the exhaust pipe plus a heat shield. 3. Install a one-way valve spring on each of the fuel pump inlet and outlet valves to increase the gas resistance of the gasoline pump. Fourth, the engine and the lubrication system In the summer, the engine is also prone to problems of the site. Therefore, the engine should also be subject to special maintenance, especially the limousine, the engine temperature is generally higher, if the outside temperature is high, the problem becomes more prominent, so the proper maintenance of the vehicle engine is very important. Summer engine should be replaced with high viscosity grade lubricants, and appropriate shortening the oil change cycle, the hub bearing grease with high dropping point, the transmission and differential for thick summer gear oil, brake fluid using boiling point higher Brake fluid. For limousines, use high quality antifreeze and engine oils, limousines should use SG (SH, SJ better) engine oil, and the oil temperature should be at least 15W40 (preferably 5W50) synthetic engine oil. In general, the use of high-quality antifreeze and high-quality oil plus reasonable operation, the summer engine failure can be avoided. Fifth, check the charge Department of summer driving, charging system should also be checked regularly. Battery prone to overcharge, the electrolyte evaporates quickly, easy to damage the plate, it should always check the battery level and the proportion of electrolyte (electrolyte proportion should be smaller than in winter), often to the electrolyte Distilled water, to keep the fill port vents open unimpeded, otherwise there will be an increase in the internal battery pressure so that the shell burst; also adjust the generator regulator, reducing the generator charging current. In short, as long as the reasonable knowledge of maintenance and driving and timely troubleshooting of common faults will make the vehicle safely pass the "sensitive period" of vehicle safety in summer.