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附录 A 英文文献与中文参考翻译In the 1970s introduced electronic controls fuel injection system with high performance, it can meet the modern automobile to except the strict request discharge, saving, increase in power, to improve performance and many other aspects accelerating its advantages, gradually replacing carburetor and extensive use, is the inevitable trend of the future.In EFI system, a fuel common faults mainly has: the ignition switch, pump, oil pump does not turn the oil pipeline, not too high or too low, hydraulic injection fuel nozzle nozzle, no oil leakage or drops of oil, fuel nozzle and tubing connection or the intake manifold junction leakage, and cold start-up nozzle doesnt work, etc. The following simple introduction of these faults and eliminate.(1)oil pump oil or notThe ignition switch, pump can turn or pump oil, the main causes of the following: (1) if the engine running, because the air flow has not moved, and the impeller of it is not connected to pump switches to L (EFI system), or distributor in speed signal transmission to the electronic controller (ECU) (EFI system for D) : 2) pump drive circuit relay or main contactor relays disconnect circuit breakers, or coil ablation, 3) pump power input, or the power plug contact undesirable conductor disconnected, 4) pump brush, brush spring break or wear loses elasticity: 5) of the armature winding burning oil: 6) pump wheels stuck. For this failure, should press following method for checking and removing: check whether the oil pump, electric in through the ignition switch engine running, not after the press the pump drive circuit switch, such as oil pump check and its driving circuit itself without fault, pump should be able to turn and oil pump. If pump, should first turn not check whether the power plug pump, or loose wires connecting the disconnect, this is the most common causes of malfunction, also more easily. Further, including driving circuit can check to the failure of the ignition switch, fuse is, the relay, power supplies, and such as relays disconnect the plug and wires connecting them. The relay contacts ablation, electromagnetic winding drive circuit broken will affect the burn, pump can rotate. If contact ablation is not serious, can repair, or by burnish should replacement parts. Final inspection pump itself, can use digital multimeter measurement of the oil pump motor armature, normally its resistance to 12 15n, if the measurement result is somewhat larger, probably due to plug, attachment areas such as poor contact, or brush wear. If the measured value is infinite, you must have been burned armature winding is broken. Because of the pump is whole package, cannot open repair, so should be replaced. After the examination, and in different parts of the normal circumstance, still appear likely engine running, dont turn pump is due to the air flow pump switches have caused by fault, switch contact undesirable, can cause failure attachment breakers. Through the inspection pump switches, easily find fault.(2)pump rotation but not pump oilPump rotation but not pump oil, mainly composed of the following reasons: 1) the pump pressure valves, or stuck roof-floor valve spring break, make discharging pressure valves, pumps have often open the oil pump flow back, but only to the tank can pump pressure pipe in fuel, 2) of the oil pump fitting stuck out of oil pump, not by pressing pressure oil pressure valves only by return tank, 3) the pump JinYou blocked, or JinYou mesh seere blockages, make the pump suction resistance due to too much and cannot pump out fuel, 4) pump impeller and pump shell with serious wear, mutual exist great gap, cannot be fuel pump. To avoid this problem, should strictly in accordance with the requirements of operation and maintenance, cleaning, cleaning tank on screen, avoid jam phenomenon. To check or discharging pressure valves, slight delay card can use the method to eliminate keystrokes and vibration. If you have severe worn or damaged parts of the situation, it should be replaced pump.(3)fuel pressure lowFrom the oil pump output to fuel pressure should be 0.27-0.30 MPa. Low pressure will seriously affect the fuel injection quantity measurement, to reduce power down, causing difficulty, starting to engine performance. Low pressure caused by the reasons for oil pump, valve, pressure from 0 - or - to valve leakage, JinYou filter clogging pump impeller and, wear, and fuel filters in oil, are the factors should be taken into consideration. Another to consider is the regulator, if the voltage regulator, the diaphragm spring is damaged, soft, seating damage caused by oil pressure will be low. If the above situation, should replace the regulator.(4)fuel pressure is too highPressure regulator is caused by excessive stiffness spring is the main reason for the high pressure difference, if the standard with excessive, will make the injection quantity, causing the mixture, now should replace pressure regulator. In addition, pressure regulator and the intake manifold connection pipe leakage, make its cannot feel intake manifold vacuum, will cause the compensating mixture too thick. Through the careful installation of connection lines and often check, can avoid such failure.(5)cold start-up nozzles.such workCheck whether the cold start nozzle can work normally, it should be removed from the inlet connection, with the special tools to coiled tubing connection with the cold start nozzle together, reoccupy interconnects socket and special tools to both the battery. Note battery anode, positive line only even in my hand, and in a very short time point of contact battery anode piles, if the cold start nozzle is good, it will be a brief jet fuel. Otherwise, shall check the cold start nozzle, main is to check whether the magnetic coil. Using a multimeter to check the magnetic coil, the resistance should be in 3-5 , if the resistance, that the magnetic coil is burning. If the cold start nozzle is good, but do not spray, should check whether the normal temperature switches. Using the multimeter to test its two ends, wiring resistance should be 20-50 , if reach 50-60 that its internal contacts have closed loop, nozzle coil current, cause not spray. Note that if the environment temperature over 40 C, the temperature of the time switch contacts open attribute normal phenomenon.
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