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ME-SFI [ME] injection regulation, function - GF07.61-P-3002G

ENGINE 273 in MODEL 463.202/222/236/237 up to 31.5.12 as of model year 2009/YoM 08 

Fig 1: Identifying ME-SFI [ME] Injection Regulation Function Chart
G07889227Courtesy of MERCEDES-BENZ USA

Function requirements for injection regulation of the ME gasoline injection and ignition system (motor electronics) (ME), general points 

ME injection regulation, general points 

The engine receives the fuel quantity required in each case from the ME-SFI [ME] control unit.

Using the performance map, the ME-SFI [ME] control unit calculates the injection time required according to the following sensors and signals:

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

ME-SFI injection regulation, function sequence 

The ME-SFI [ME] control unit controls the injection time in the following operating conditions:

Partial load operation function sequence 

In partial load operation when the engine is warm, the ME-SFI [ME] control unit calculates the actuation time of the injection valves (Y62) according to the lambda control and the engine torque requirement.

Full-load operation function sequence 

In full-load operation when the throttle valve is fully open, the ME-SFI [ME] control unit extends the actuation time of the fuel injection valves in order to ensure maximum engine torque.

IMPORTANT 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 valve also opens and closes rapidly. This causes the mixture to become briefly leaner or more rich.

To prevent this, the ME-SFI [ME] control unit 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.

  Component description for ME-SFI [ME] control unit N3/10 GF07.61-P-6000G