Injection Regulation, Function - GF07.10-P-1004KJ

ENGINE 281.910 in MODEL 453.0/3/4 

Function requirements for injection regulation, general points 

• Circuit 87 (Engine management ON)
• Engine runs

Injection regulation, general points 

The ME-SFI [ME] control unit (N3/10) assigns the required fuel quantity to the engine.

Using the characteristic map, the ME-SFI [ME] control unit calculates the injection period and pressure based on the following signals:

• Intake camshaft Hall sensor (B6/15), intake camshaft setting
• Coolant temperature sensor (B11/4)
• Intake air temperature sensor (B17)
• Charge air temperature sensor (B17/8)
• Pressure sensor downstream of throttle valve (B28/7), engine load
• Accelerator pedal sensor (B37), driver engine load request
• Accelerator pedal sensor, accelerator pedal operation (fast or slow) (for acceleration, in decel mode or for braking)
• Oxygen sensor upstream of catalytic converter (G3/2)
• Crankshaft position sensor (L5), engine speed
• Atmospheric pressure sensor in ME-SFI [ME] control unit, altitude adaptation
• Correction programming of the adaptation values with XENTRY Diagnostics

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

Function sequence for injection regulation 

The ME-SFI [ME] control unit controls the injection period under the following operating conditions:

• Function sequence for partial load and wide open throttle operation 
• Function sequence for acceleration 

Function sequence for partial load and wide open throttle operation 

In the ME-SFI [ME] control unit the actuation time of the cylinder 1 injection valve (Y62/1) up to cylinder 3 injection valve (Y62/3) is calculated dependent on the lambda control and the requested engine torque.

At the accelerator pedal sensor, about 0 to 90% slewing range is defined as partial load and more than about 90% slewing range is defined as wide open throttle.

Function sequence for acceleration 

When there is rapid change in the accelerator pedal position, the throttle valve also opens and closes rapidly. This causes the mixture to become briefly leaner or too rich.

To prevent this, the ME-SFI [ME] control unit adapts the fuel/air mixture by lengthening or shortening the actuation time of the cylinder 1 injection valve to cylinder 3 injection valve dependent on a characteristics map. This prevents jerking of the engine.

	Electrical function schematic for injection control		PE07.10-P-2704-97BBA
	Overview of system components motor electronics (ME-SFI) fuel injection and ignition system		GF07.61-P-9997KJ