Nozzle injector nozzle itself is a normally closed valve.
1, the principle of nozzle
is actually a simple injector solenoid valve, when the solenoid is energized, a suction force, is sucked from the needle, the injection hole is opened, the fuel by the needle an annular gap between the pintle and the high-speed ejection orifices of the head to form a mist, facilitates complete combustion.
2, nozzle effect
gasoline Direct injection the most delicate part of the engine – nozzle
as one of the key components of the injector EFI engine, it is good or bad work performance will be severely affected by the engine. Nozzle blockage will seriously affect vehicle performance. Blockage of the engine due to coke deposition on the fuel injector or due to the impurities clogging the nozzle passageway. After driving the car for some time, it will form a certain fuel system deposits. Formation of deposits and automotive fuel directly related: First, because the gasoline itself contains resin, impurities, or during storage into the dust, impurities, etc., accumulate and form a deposit in a similar sludge tank cars, and other parts of inlet pipe thereof; secondly due to the unstable gasoline component react at a certain temperature, the formation of gum and resin-like dope. The dope in the fuel injectors, intake valves and other parts, when burning coke deposits will become hard. In addition, due to urban traffic congestion, often in low speed and idling car state, but will increase the formation and accumulation of these deposits. Great harm fuel system deposits. Deposits clog the nozzle needle, the valve hole, affect the performance of precision electronic injection system components, resulting in dynamic performance degradation; coke deposits formed in the intake valve, resulting in its closed tightly, causing the engine idle speed stability, increased fuel consumption and associated emissions deterioration; hard coke deposits formed in the piston crown and the cylinder head and other parts, due to the high thermal capacity and poor thermal conductivity of the coke, prone to engine knock and other faults; in addition also shortens three yuanLife of the catalyst. Injectors work is good or bad, for each engine power plays a fundamental role to play. Due to poor fuel injector work not working cause the cylinder coke serious; cylinder, piston ring wear accelerated, resulting in unstable idle speed, increased fuel consumption, accelerate weakness, difficulty starting and emissions exceeded, serious will be completely clogged spray nozzle, damage to the engine. Therefore, regular cleaning fuel injectors, long periods of cleaning or frequent cleaning nozzle will cause a bad influence. As a matter of time cleaning, to be determined according to the quality and condition usually add fuel, in general, most recommend that users now about 20,000 to 30,000 km for cleaning. Good condition, good quality fuel can be extended to about 4 to 60,000 km. When the nozzle clogging slightly, also have some impact on vehicle condition. Sometimes there will be such a failure: hang a block, start the car some jitter, etc. upshift during acceleration, this phenomenon disappeared, assuming various sensors working properly the car, valve is also cleaned, the circuit is also normal , it is likely that a slight blockage of the nozzle. But when high gear acceleration, there is likely to be mild gum has been sprayed away (dissolved), and vehicle performance resumed. This small plug nozzle, generally can not clean. Because of minor gum can be dissolved away. Therefore, in daily driving, you should always run a high-speed run, in order to reduce the possibility of coke into lines. When poor quality gasoline or a longer running time of the vehicle, if long periods of cleaning nozzle, this clogging will be more severe, causing poor engine fuel injection, injection angle and poor atomization, causing the engine idling, acceleration or full load condition when the work is not good, so that the engine power drop, increased fuel consumption, increased pollution emissions, even the engine does not work. Therefore, the detection nozzle should be regularly cleaned carefully to ensure good working order.
3, when the need cleaning nozzle
When selecting the specific needs require cleaning – Control the number of the fuel injection amount: of the same type of electrical spraying vehicles, fuel pump pressure is constant, regardless of the degree of throttle opening size, as long as a regulated fuel pressure regulator, fuel injector pressure is always constant. injector and fuel pump and a fuel pressure regulator deviceOnly the design pressure, nozzle in order to meet stringent supporting the use of the best atomization, pressure is lower than the design pressure, spray mist of oil is not, columnar, should not be mixed with air; too much pressure, spray oil tapered circular shape, are not easy to mix, and the ejection force is too large, a lot of fuel directly sprayed onto the wall, the mixing ratio directly affects the parameters. Whether it is accelerating or idling, the pressure should be constant. Different models pressures are also different. (There are a few block select washing machine friend mentioned, in fact, is the pressure for different models of choice, not accelerated idling of different pressure, the selected error injection pressure, nozzle atomization bad). how much fuel injection quantity, injection time depends on the length of the injector according to the different control solenoid, and the divided voltage driven current driven two species, can be divided into low resistance and voltage-mode high impedance, high impedance can be electrically connected to 12V, low resistance only by a low voltage, 12V misconnection time in the coil will burn longer. when the fuel injection, the voltage provided by the computer is constant, for example 12V, fuel cut immediately becomes 0V, the change is instantaneous, 01 like a computer language concepts and inside, the intermediate did not say 0.5. in other words, this is a pulsed DC signal . AC, etc. What is not a class of nouns, AC concept? alternating positive and negative called staggered as if inside the car in addition to the generator rectifier previous section, basically the reach of the AC. when the nozzle clogging, fuel injection poor, or there is a gap nozzle Carbon glue and was less than the design of the fuel injection amount or atomizing effect, it needs to be cleaned.
4, the step of washing
1, remove the rail fixing screws
2, tentative shaking rail and remove it, to avoid damage to the nozzle seal
3, the negative electrode of the battery is always guaranteed OFF
4, the spray remove the oil from the nozzle rail
5, with homemade injector nozzle is connected to the plug and wire
6, pressure of cleaning agent in place of the actual work oil pressure
7, remain connected to the positive wire and reviews
8, the head of nozzleWashing
9, when mounting rail, to be noted that the position of the injector nozzle and a sealing ring clamp
5, injector Common Troubles
a, ejection clogging. Available through the needle to clear, to clear the weft carefully after cleaning. Needle valve body and the nozzle body large flat planar contact failure, wear, or needle larger cylindrical surface. If the needle valve body and the nozzle body large flat plane is bad, it can be used for chromium oxide coated on the plate “8” shape grinding; cylindrical surface wear greater if the needle, the needle coupling parts should be replaced as a pair.
Second, the needle body and needle seal failure, resulting in poor atomization or nozzle drip. This failure can be used fine chromium oxide or toothpaste applied to the needle end of the sealing tape, but do not applied to the cylindrical portion, then the insertion needle of the needle valve body side until knocking side turn adhesion. Chromium oxide grinding stone must be washed away or toothpaste.
Third, the air in the oil passage. Simply oil in the air can be excluded.
Fourth, the fuel supply is not normal output. The need for fuel pump maintenance. As a result of the joint pipeline leak, may try to take a good, it does not leak.
Fifth, the lack of spring force of the piston or spring break. Should replace the spring.
Sixth, the wear of the piston with oil. Pistons need to be replaced.
6. References
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