ME-SFI injection regulation, function - GF07.61-P-3002MIS
ENGINES 272.9 in MODEL 221.0 /1 as of model year 2009/ YoM 08
ENGINES 273.9 in MODEL 216.3, 221.0 /1 as of model year 2009/ YoM 08
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 [ME] control unit (N3/10).
Using the performance map, the ME-SFI [ME] control unit calculates the injection time required according to the following sensors and signals:
- Hot film MAF sensor (B2/5), engine load
- Intake air temperature sensor (B2/5b1)
- Coolant temperature sensor (B11/4)
- Pressure sensor (B28), intake manifold air pressure
- Intake manifold LH tumble flap position sensor (B28/9), LH tumble flap position
- Intake manifold RH tumble flap position sensor (B28/10), RH tumble flap position
- 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
- Accelerator pedal sensor (B37), driver engine load request
- Accelerator pedal sensor, accelerator pedal operation (fast, slow) (when accelerating)
- Crankshaft Hall sensor (B70), engine speed
- LH O2 sensor upstream of CAT (G3/3), oxygen sensor signal
- RH O2 sensor upstream of CAT (G3/4), oxygen sensor signal
- Altitude pressure sensor in ME-SFI [ME] control unit, atmospheric pressure for altitude adaptation
- Engaged intake manifold length
- Correction programming with the DAS (during acceleration)
The requirements of the engine torque requirement function are also taken into account.
Hybrid vehicles The tumble flaps and the associated sensors are installed for hybrid vehicle but are not and are therefore without function.
Function sequence for injection regulation
The ME-SFI [ME] control unit controls the injection time in the following operating conditions:
- Function sequence for partial load operation
- Function sequence for full-load operation
- Function sequence for acceleration
Function sequence for partial load operation
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.
Function sequence for full-load operation
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.
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.
Function sequence for acceleration
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.
The ME-SFI [ME] control unit therefore adapts the fuel-air mixture by lengthening/shortening the actuation time of the fuel injection valves according to a performance map.
This prevents jerking of the engine.
| Electrical function diagram for injection control | Model 216 | PE07.61-P-2788-97CAB | ||
| Component description for ME-SFI [ME] control unit | N3/10 | Engine 273 | GF07.61-P-6000MLS | |