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GF07.61-P-3002MAR ME Injection Regulation, Function



GF07.61-P-3002MAR ME Injection Regulation, Function
- refinement package
- as of model year 09


Function requirements for injection regulation, general points
^ Circuit 87M ON (engine control ON)
^ Engine running

Injection regulation, general points
The engine receives the fuel quantity required in each case from the ME-SFI control unit (N3/10).

Using the performance map, the ME-SFI control unit calculates the injection time required according to the following sensors and signals:
- LH and RH hot film MAF sensor (B2/6, B2/7), engine load
- Fuel pressure sensor (B4/15)
- LH and RH intake camshaft Hall sensors (B6/4, B6/5), intake camshaft positions
- LH and RH exhaust camshaft Hall sensors (B6/6, B6/7), exhaust camshaft positions
- Coolant temperature sensor (B11/4)
- Intake air temperature sensor (B17) (only during warm-up)
- Pressure sensor (B28), intake manifold air pressure
- Accelerator pedal sensor (B37), driver engine load request
- Accelerator pedal sensor, accelerator pedal activity (fast, slow) (for acceleration)
- Crankshaft Hall sensor (B70), motor speed
- LH and RH O2 sensors upstream of CAT (G3/3, G3/4), oxygen sensor signals
- Altitude adaptation pressure sensor in the ME-SFI control unit, atmospheric air pressure
- Engaged intake manifold length
- Correction programming with the DAS (during acceleration)

The requirements of the engine torque requirement function are also taken into account.

Injection regulation function sequence
The ME-SFI control unit controls the injection time in the following operating conditions:
^ Partial load operation function sequence
^ Full-load operation function sequence
^ Acceleration function sequence

Partial load operation function sequence
In partial load operation when the engine is warm, the ME-SFI control unit calculates the actuation time of the fuel injection valves (Y62) according to the lambda control and the required engine torque.

Full-load operation function sequence
In full-load operation when the throttle valves are fully open, the ME-SFI control unit extends the actuation time of the fuel injection valves in order to ensure maximum engine torque.

About 10 to 90% of the slewing range on the accelerator pedal sensor is partial load and more than about 90% of the slewing range is defined as full load.

Acceleration function sequence
When there is rapid variation of the accelerator pedal position, the throttle valves open and close rapidly. This causes the mixture to become briefly leaner or more rich.
The ME-SFI control unit therefore adapts the fuel-air mixture, by lengthening or shortening the actuation time of the fuel injection valves according to a performance map. This prevents jerking of the engine.