Gasoline Injection And Ignition System With Direct Injection, Function - GF07.70-P-0002MRA
Engine 274.9 in Model 205 (except 205.047/053/054/147/247/253)
Engine 274.9 in Model 253 (except 253.354/954)
Networking via direct lines
CAN networking, up to Model year 2019
CAN networking, Model 205 as of Model year 2019, Model 253.99
Gasoline injection and ignition system with DI, general
The gasoline injection and ignition system with direct injection in electrical combination with the sensors and actuators of the engine M 274 forms the engine management "MED40".
The short designation "MED40" stands for:
M = Motronic
E = Electronics
D = Direct injection
4 = 4 cylinder
0 = generation 0
The whole engine management is contained in the ME-SFI control unit. Sensor data are read in directly by the engine management and indirectly via the CAN network and the respective actuators are actuated. The individual functions and systems of the engine management are controlled and coordinated by the ME-SFI control unit.
The engine management is subdivided into the following systems:
- Basic functions
- Engine system
- Fuel injection system
- Ignition system
- Exhaust system
- Exhaust gas recirculation (with code 920 (Gasoline direct injection with stratified charge))
Basic functions
- Control module programming
- Control unit diagnosis
- European On-Board Diagnosis
- DAS stage 4 (FBS 4)
- Torque coordination
- Heat management
- Alternator interface
- Maximum vehicle speed limit
Diagnosis:
For diagnostic purposes, the fault codes of the engine management system can be read out and deleted and individual diagnostic functions can be specifically actuated.
The ME-SFI [ME] control unit exchanges data with other control units via the connected drive train CAN and engine CAN which are integrated into the CAN network.
Control unit programming:
The engine management in the ME-SFI [ME] control unit is programmable, i.e. the software of the control unit can be exchanged (replaced). The software required for control unit programming can be found on the diagnosis system software DVD.
Transport mode:
In transport mode various functions of the engine management are limited. If the kilometer reading of the vehicle is more than 250 km, the "transport mode" system status is automatically deactivated and can also no longer be reactivated.
Variant coding:
The vehicle model, national version, exhaust variant and transmission version, for example, can be coded with the variant coding.
Engine system
- Starter relay actuation
- Throttle valve control
- Safety fuel shutoff
- Transmission overload protection
- Support of the Electronic Stability Program (ESP®)
- Fully integrated transmission control assist (automatic transmission)
- Driving on torque limitation
- Fan operation
- Boost pressure control (over wastegate)
- Regulated adjustment of the intake and exhaust camshaft
- ECO start/stop function
Fuel injection system
- Fuel pump controlling (low fuel pressure)
- Gasoline high pressure regulation
- Cylinder-selective DI
- Start, post-start phase and acceleration enrichment
- Warm-up control
- Idle speed control
- Inertia fuel shutoff
- Altitude adaptation (integral pressure sensor in ME-SFI control unit)
- RPM limitation
- RPM increase for an activated A/C
- Load change function
- Limp-home function
Ignition system
- Multi-spark ignition
- Ignition map
- RPM limitation
- Knock sensor system
- Synchronization of camshaft and crankshaft position
Exhaust system
- Catalytic converter heating
- Oxygen sensor heater controlling
- Straight-line lambda control
Exhaust gas recirculation (with code 920 (Gasoline direct injection with stratified charge))
- Exhaust gas recirculation valve regulation
- Purging the NOx storage catalytic converter
Homogeneous operation
In homogeneous mode an homogeneous combustible fuel/air mixture (λ = 1) is generated within the whole combustion chamber. There are no further measures required for exhaust aftertreatment since the normal three-way catalytic converter adequately converts the pollutants.
Engine 274.9 in Model 205 (except 205.047/053/054/147/247/253) with code 920 (Direct gasoline injection with stratified charging)
Engine 274.9 in Model 253 (except 253.354/954) with code 920 (Direct gasoline injection with stratified charging)
During stratified operation, a combustible mixture (λ ≈ 1) is present only in the vicinity of the spark plug while various lambda values are present in the remaining combustion chamber. This varies from pure intake air through to exhaust gases from the EGR. Thus fuel consumption in stratified operation is less than that in homogeneous mode. Because of the excess air, which consists of approx. 75 % nitrogen, the NOx development in the stratified charge operation is significantly higher than in the homogeneous injection operation. This requires use of a NOx storage catalytic converter.
In homogeneous stratified charge operation, more favorable exhaust emission values can be achieved above 4 bar injection pressure than in pure stratified charge operation. At the same time, it enables an injection pressure of more than 7 bar, as a result of which considerable savings in consumption are achieved. Homogeneous stratified charge operation is a combination of homogeneous/lean and conventional stratified combustion systems. Here, with a non-derated engine, the first injection tales place in the intake stroke; the actual "stratified" injection takes place before the ignition.
| Crankcase ventilation system, function | GF01.20-P-0001MRA | ||
| Ignition ON, function | GF07.10-P-1000MRA | ||
| Starting, function | GF07.10-P-1001MRA | ||
| Ignition OFF, function | GF07.10-P-1002MRA | ||
| Fuel supply, function | GF07.10-P-1003MRA | ||
| Injection regulation, function | GF07.10-P-1004MRA | ||
| Ignition system function | GF07.10-P-1005MRA | ||
| Synchronize fuel injection and firing order function | GF07.10-P-1006MRA | ||
| Start, post-start phase and warm-up enrichment, function | GF07.10-P-1007MRA | ||
| RPM control, function | GF07.10-P-1008MRA | ||
| Alternator interface function | GF07.10-P-1009MRA | ||
| Lambda control, function | GF07.10-P-1010MRA | ||
| Smooth running control, function | GF07.10-P-1011MRA | ||
| Thermal management, function | GF07.10-P-1012MRA | ||
| Torque coordination, function | GF07.10-P-1013MRA | ||
| Overrun mode fuel shutoff, function | GF07.10-P-1014MRA | ||
| Knock control, function | GF07.10-P-1015MRA | ||
| Camshaft adjustment, function | GF07.10-P-1016MRA | ||
| Engine limp-home mode, function | GF07.10-P-1019MRA | ||
| On-board diagnosis, function | GF07.10-P-1020MRA | ||
| ECO start/stop function engine management, function | GF07.10-P-1042MRA | ||
| Charging, function | GF09.00-P-2000MRA | ||
| Exhaust treatment function | GF14.00-P-3000MRA | ||
| Exhaust gas recirculation, function | Engine 274.9 in Model 205 (except 205.047/053/054/147/247/253) with code 920 (Direct gasoline injection with stratified charging) Engine 274.9 in Model 253 (except 253.354/954) with code 920 (Direct gasoline injection with stratified charging) |
GF14.20-P-3000MRA | |
| Electronic accelerator function | GF30.20-P-3015MRA | ||
| On-board refueling vapor recovery function | Engine 274.9 in Model 205 (except 205.047/053/054/147/247/253) with code 494 (US version) Engine 274.9 in Model 253 (except 253.354/954) with code 494 (US version) |
GF47.10-P-3004MRA | |
| Purging function | GF47.30-P-3015MRA | ||
| Purging system with leak test function | Engine 274.9 in Model 205 (except 205.047/053/054/147/247/253) with code 494 (US version) Engine 274.9 in Model 253 (except 253.354/954) with code 494 (US version) |
GF47.30-P-3016MRA | |
| Overview of system components for gasoline injection and ignition system with direct injection | GF07.70-P-9998MRA |