Injection Regulation, Function - GF07.10-P-1004MNA
Engine 177.9 in model 205, 253
Engine 177.9 in model 213
up to model year 2021
Function requirements, general
- Engine runs
The ME-SFI [ME] control unit (N3/10) detects that the engine is running by interpreting the signals from the crankshaft Hall sensor (B70). The ME-SFI [ME] control unit directly reads in the signals of the crankshaft Hall sensor.
Injection control
The injection control distributes the required fuel quantity to each cylinder in a demand-based way. The fuel quantity results from the injection duration and the injection pressure when doing this. The ME-SFI [ME] control unit computes the injection duration and the injection pressure based on the signals from the following sensors:
- Right fuel pressure and temperature sensor (B42/1)
- Left fuel pressure and temperature sensor (B42/2)
- Left intake camshaft Hall sensor (B6/4)
- Right intake camshaft Hall sensor (B6/5)
- Left exhaust camshaft Hall sensor (B6/6)
- Right exhaust camshaft Hall sensor (B6/7)
- Coolant temperature sensor (B11/4)
- Left charge air temperature sensor (B17/14)
- Right charge air temperature sensor (B17/15)
- Pressure sensor downstream of left throttle valve (B28/22)
- Pressure sensor downstream of right throttle valve (B28/23)
- Accelerator pedal sensor (B37) (model 205, 253)
On model 213 the powertrain control unit (N127) directly reads in the signals from the accelerator pedal sensor and sends them via the drive CAN (CAN C1) to the ME-SFI [ME] control unit.
- Crankshaft Hall sensor
- Left oxygen sensor upstream of catalytic converter (G3/3)
- Left oxygen sensor element upstream of CAT (G3/3b1)
- Right oxygen sensor upstream of catalytic converter (G3/4)
- Right oxygen sensor element upstream of CAT (G3/4b1)
- Atmospheric pressure sensor in the ME-SFI [ME] control unit
The requirements of the torque coordination function are also taken into account.
The ME-SFI [ME] control unit distributes the required fuel quantity to each cylinder by actuating the following component parts:
- Cylinder 1 fuel injector (Y76/1)
- Cylinder 2 fuel injector (Y76/2)
- Cylinder 3 fuel injector (Y76/3)
- Cylinder 4 fuel injector (Y76/4)
- Cylinder 5 fuel injector (Y76/5)
- Cylinder 6 fuel injector (Y76/6)
- Cylinder 7 fuel injector (Y76/7)
- Cylinder 8 fuel injector (Y76/8)
The ME-SFI [ME] control unit makes a distinction between the following operating conditions when doing this:
- Engine start
- Idle speed
- Partial load, full load
- Accelerate
The operating conditions "engine start" and "idle" are described in separate documents.
Partial load, full load
The ME-SFI [ME] control unit calculates the actuation time of the fuel injectors depending on the lambda control, the fuel pressure in the rails and the requested engine torque.
At the accelerator pedal sensor (B37) a slewing range of 10 to 90 % is defined as partial load and more than 90 % as full load.
Multiple injection
With multiple injection, the fuel injectors are actuated multiple times in succession. The injection quantity is distributed to multiple single fuel injections.
Multiple injections can occur with the following actions:
- Heat up catalytic converters
- Combustion stabilization at high loads and speeds of more than 2000 RPM
Multiple injection takes place during engine start up or during long idle phases to keep the catalytic converters warm.
Accelerate
When there is rapid change in the accelerator pedal position, the throttle valves open or close 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 fuel injectors according to a characteristics map. This prevents jerking of the engine.
| Electrical function schematic for injection control | Engine 177.9 in model 205, 253 | PE07.10-P-2704-97FBD | |
| Engine 177.9 in model 213 up to model year 2021 | PE07.10-P-2704-97DBG | ||
| Overview of system components for gasoline injection and ignition system with direct injection | Engine 177.9 in model 205, 253 | GF07.70-P-9998MNA | |
| Engine 177.9 in model 213 up to model year 2021 | GF07.70-P-9998MNE |