汽车发动机电控技术(Automotive engine electronic control technology)

汽车发动机电控技术（Automotive engine electronic controltechnology）1. Fill in the blanks1. China has issued a notice on June 27, 2001, after July 1, 2001, canceling the production of carburetor type engine, and suspending the production of 187 kinds of carburetors and 5 passenger cars.2. Development of automotive electronic control technology. From the mid-1960s to the mid-1970s; In the late 1970s and mid-1990s, the two phases of mechanical electronic control were developed. Since the mid-1990s, there are three phases of development of automotive electronics.3. In the electric fuel injection (EFI) system, the ECU determines the fuel injection volume according to the intake volume, and according to the signal to the oil injection quantity correction, the engine obtains the optimum concentration of the mixture.4. Ignition control system (ESA) function is the ignition advance Angle control.5. The idling control system (ISC) function is to control the intake volume by controlling the idle speed.6. The air intake control system is based on the engine speed and load and controls the intake.7. Emission control includes exhaust gas recirculation (EGR) control, activated carbon can solenoid valve control, oxygen sensor and closed-loop control, secondary air injection control.8. The control system automatically presses the reference signal value set by the computer when failure protection system function fails.9. The emergency standby system function is to control the engine to the forced operation according to the programmed signal when the system fails.10. The electric control gasoline injection system is provided by air supply system, fuel oil supply system, ignition control system and electronic control system.11. Two basic types of electronic control system are open-loop control system and closed-loop control system.12. Oil injector position: cylinder injection and cylinder ejection. Fuel injection sequence: sequential injection, group injection and simultaneous injection. Injector number: single point jet and multi-point injection.13. The type of sensor, air flow meter, inlet absolute pressure sensor, throttle position sensor, crankshaft position sensor (CAM), coolant temperature sensor, speed sensor, air intake temperature sensor, oxygen sensor, knock sensor.14. Engine ECU gives the sensor 2V, 5V, 9V or 12V voltage.15. Actuators are: fuel injector, igniter, idle speed control valve, cruise control electromagnetic valve, throttle control motor, EGR valve inlet valve, secondary air injection valve, activated carbon tank discharge solenoid valve, pump relay, relay fan, air conditioning compressor relay, self-diagnose display and alarm device, instrument display, etc.16. Asynchronous injection timing control: when starting, an asynchronous injection is added in addition to synchronization; When accelerating, add a fixed injection amount.17. Duration of fuel injection (duration of basic injection) X (oil injection correction factor) + voltage correction value18. D-type electric control fuel injection system, ECU determines the fuel injection time according to the speed signal Ne and the inlet pipe absolute pressure signal PIM.19. L-type electric control fuel injection system, the ECU determines the fuel injection time according to the speed signal Ne and the air flow meter signal VS.20. Fuel stop for control: decelerate oil control and speed control.21. In the electric fuel injection system, the fuel pump generally works 2-3s in advance or delayed to ensure system oil pressure.22. The function of the air supply system: to measure andcontrol the amount of air necessary for engine combustion.23. Composition of air supply system: air filter, ventilation hose, air flow meter, throttle body, idle speed control valve, intake manifold and intake pressure sensor. Type D EFI and L - type EFI systems.24. Inlet temperature sensor: turns the measured inlet temperature into an electrical signal.25. The function of idle control valve: one, stabilize engine idle speed, reduce fuel consumption; When the load increases, increase the idle speed to prevent the engine from flameout.26. Principle of stepping motor: the ECU controls the coils of motor coils, the stator turns clockwise and the rotor is rotated with the stator field. Stator 32 grab pole (upper and lower the 16) so motor per round for 11 ° Angle. The step motor has a range of 0 to 125 steps.27. Electric fuel oil pumps can be divided into two types: internal and external. Mainly consists of filter, one-way valve, safety valve, oil pump, and dc motor.28. Type of electric fuel oil pump: turbine type, roller type, gear type and side tank fuel pump.29. The general automobile should replace the fuel filter for each 20,000-40,000km or 1-2 years, and the fuel system pressure will be released at the first time.30. The role of the oil pressure regulator is to eliminate the fluctuation of the oil pressure pressure and adjust the range of oil pressure in the system between 250 and 400 Kpa.31. Absolute pressure of spray oil = spring pressure (fuel pressure regulator)32. The fuel injector generally installed on the intake manifold, low resistance injector for 2-3 Ω, high value should be 13 -- 16 Ω. The oil spray is generally 50-70ml \ 15s, and the rate of the oil spray of each cylinder is not more than 10%.33. In order to ensure reliable ignition, the ignition system generally requires a reliable supply of 50-80mj, with a maximum of 150mj ignition energy.34. The best ignition advance Angle should be on the highest pressure inside the engine cylinder in 10 °, 15 ° after the check point.35. The electric control ignition system consists of power supply, sensor, ECU, ignition coil, distributor, spark plug and so on.36 G signal: refers to the piston runs to the top dead center position of the signal, is commonly before the check point on 70 °.37. Ne signal: refers to the engine crankshaft Angle signal.38. IGt signal: refers to the control signal sent by the powertransistor in the ECU to the ignition.39. IGf signal: refers to the ignition confirmation signal transmitted to the ECU after the ignition is completed. When the engine is working, the ECU sends IGf signal to the IGf. If there are three or five failed IGf signals, the ECU will judge that the ignition system is faulty, and stop the fuel injection to cause the engine to stall.40. A distributor of electronic control ignition system sensor are: the camshaft, crankshaft position sensor, air flow meter (intake manifold absolute pressure sensor), coolant temperature sensor, throttle position sensor, speed sensor, etc.41. The electric control ignition system can be divided into independent ignition mode, ignition mode and diode distribution ignition mode.42. EGR rate = (EGR flow) divided by (inhalation of air quantity + EGR flow) times 100 percent. No EGR is performed when idle and low loads.43. The three-way catalytic converter can not only further oxidize harmful gases such as HC and CO in the exhaust gas to generate harmless carbon dioxide and water,It can also induce NOx and CO in the exhaust gas to produce harmless carbon dioxide and nitrogen. The best working area of the catalyst is 14.7.The zirconium oxide sensor is a chemical cell, also known as a differential oxygen concentration cell. The oxygen sensor outputs a voltage signal that has a mutation.45. The function of the secondary air supply system: under certain working conditions, fresh air is sent into the exhaust pipe, which will further oxidize the CO and HC in the exhaust gas, thus reducing the emission of CO and HC. HC + CO + O2 - (800-900 °)? The CO2 + H2O46. The obd-ii system is the most widely used self-diagnosis system.Short-answer questions(1) how to check the fuel pumpA: 1. Use a special wire to test the terminal of the fuel pump on the diagnosis seat to the 12V power supply.Switch the ignition switch to "ON" position, but don't start the engine.3. The cover should be able to hear the sound of the fuel pump working or the pressure of the hose should be felt.4. If you can't hear the sound of the fuel pump and no pressure in the inlet, repair or replace the fuel pump.5. If there is no fault in the fuel pump, if the above method is checked, it shall check whether the fuel pump circuit wire,relays, fusible wires and fuse are broken.(2) the influence of electric control technology on engine performanceAnswer: 1. Improve engine power.2. Improve fuel economy of the engine.Reduce emissions.4. Improve engine performance.5. Improve engine acceleration and deceleration performance.(3) function of ECU of electronic control unitAnswer: 1. Provide the sensor with standard 2V, 5V, 9V or 12V voltage to receive input of various sensors and other devices, and replace the input information with digital signal.2. To store the characteristic parameters and relevant data information required in the operation.3. Determine the procedure required to calculate the output instruction, and calculate the output value according to the input signal and the related program.4. Compare the output signal and output command signal with the standard value, confirm and store the fault information.5. Output instructions to the actuator, or output the stored information according to the instruction.6. Learning function.(4) manual static reading of engine failure code stepsAnswer: 1. Confirm that the throttle is fully closed, the transmission is placed in "N", close the whole electric appliance, turn on the ignition switch but not start the engine.2. Cross-connect diagnostic TE1 and E1.3. Read the "CHECK ENGINE" blinking code directly from the dashboard; If there is no fault, the light will blink at intervals, and the time of light and extinguishing will be 0.25 s. The output is normal code.4. Clear engine failure code. If you want to clear the fault code, just remove the EFI fuse in the fuse box and then reload it.。