Gasoline injection control process?

When the EFI engine is working, it needs to obtain data from various sensors at any time, and then it is calculated by the driving computer and sent to the executive part for adjustment to realize the control of the engine. Simply put, it can be divided into the following situations: (only for EFI engines)

1. Stop: When you turn the key to the on position, the trip computer starts self-checking all sensors and actuators, and at the same time turns on the relay of the gasoline pump to supply oil. At this time, if the car is quiet, you will hear the sound of the electronic oil pump turning in the fuel tank. After about 1-2 seconds, when the oil pressure reaches the standard pressure, the gasoline pump stops running. At the same time, the computer will supply power to the idling stepping motor at the throttle to make it enter the normal position. At this time, turn the key to the starting position, turn on the starting relay, and the starter starts to rotate;

2. Idle speed: After the starter starts to rotate, the computer begins to read the readings of the crankshaft position sensor located on the engine flywheel and the synchronous sensor located on the distributor. If the readings are normal and the changes of the two signal data are consistent with the starting conditions, the computer will adjust the idle stepper motor and adjust the idle adjusting lever to a proper position according to the current engine cooling water temperature and intake manifold air temperature data. After everything is ready, the computer starts to calculate the ignition timing according to the signals of the crankshaft position sensor and the synchronous sensor, and calculates the opening time slot (pulse) of the oil nozzle according to the data of the water temperature sensor and the air temperature sensor, and then starts to supply power to the low voltage line and the oil nozzle line of the high voltage package according to the calculation results, wherein the power supply to the oil nozzle is carried out by pulse. According to the above principle, it is not necessary to start the EFI vehicle in freezing weather, otherwise the driving computer will calculate the opening data of solar terms, which will affect the starting effect. After the ignition is successful, the driving computer will monitor the data of each sensor at all times, and adjust the starting pulse of the idle motor and the fuel injector according to the vacuum pressure value transmitted by the absolute pressure sensor of the intake manifold installed on the engine, combined with the signals such as water temperature and intake temperature, so as to control the speed at the lowest stable speed;

3. Acceleration: When you step on the accelerator, the computer reads the value from the accelerator position sensor on the accelerator in time, calculates the vehicle load information by combining the absolute pressure (vacuum degree) sensor of the intake manifold on the accelerator and the driving speed sensor on the transfer case (202 1 Cherokee), adjusts the fuel injection pulse of the fuel injector (actually, prolongs the fuel injection time), and increases the fuel injection quantity to complete the acceleration action;

4. Deceleration: When you release the throttle, the computer will adjust the fuel injection pulse to achieve deceleration according to the signals of various sensors, but at this time, in order to ensure a smooth deceleration effect, the computer will control the fuel injection quantity and will not reduce it to a very low level. When you release the accelerator and press the brake pedal again, the computer will get a signal from the brake switch under the brake pedal. In this case, the computer will stop the fuel injector to produce the best engine braking effect, and at this time, the computer will adjust the idle motor to a suitable position to ensure that fuel injection will start when the engine speed is low to a suitable position to ensure that the engine will not stall.