Fuel Injection, Basic Function

Fuel Injection, Basic Function

1. Basic calculation of fuel mass/combustion
The current air mass/combustion is divided by 14.7 and sent to box 2. The unit is now mg fuel/combustion.







2. Compensation
In the case of a cold engine, shortly after starting, rapid load changes, knocking or a high load, the current value is multiplied by a compensation factor.

3. Closed loop
The closed loop control system value is also used as a multiplier. The value is sent to box 4.

4. Correction for purging
Multiply by the value for purging adaptation. The value is sent to box 5.

5. Multiplicative adaptation
The multiplicative adaptation value is also used as a multiplier and the new value sent to box 6.

6. Additive adaptation.
The additive adaptation value is added. If the engine is running the new value is sent via box 7 to box 8.

7. Starting fuel quantity
If the engine still has not started the starting fuel is selected. The value is sent to box 8 via box 7.

8. Fuel mass/combustion to be injected
Fuel mass/combustion is the fuel mass that is to be supplied to the engine. The value is sent to box 9.







9. Injector opening time
Converts the value into the time the injector must be open and the new value is sent to box 10.

10. Injection twice per combustion
Before the camshaft position has been detected, injection takes place twice/combustion. Injection duration is then divided by two. Current value is sent to box 11.

11. Voltage-dependent needle lift time added
Add the injector duration delay, which is voltage dependent. The value is sent to box 12.

12. Fuel shut-off
If fuel shut-off is not active, the value will be sent to box 13.

13. Activation of injector
At a specific crankshaft angle, the microprocessor controls the transistor for the injector that is next in the firing order.