ME-SFI Start Quantity Control Function

ME-SFI Start Quantity Control Function




Shown on Engine 119 in Model 210
B11/4 Coolant temperature sensor
K40 Relay module (up to 2/97)
L5 Crankshaft position sensor
M16/1 Electronic accelerator (EA)/cruise control (CC)/idle speed control (ISC) actuator
N3/10 ME-SFI control unit
Y62 Injectors (LH-SFI, HFM-SFI, PEC [LH, HFM, PMS])

Task
In order to facilitate starting of the engine when cold, additional fuel must be injected during engine start operation, depending on the coolant temperature. The increased quantity of fuel injected is achieved by extending the injection time.

Design/function
The start quantity control is dependent on:
- Start recognition
- Coolant temperature
- Engine speed
- Engine shutoff time
- Altitude on engine 137 and engine 112, 113 with ME 2.8

The start quantity control is enabled after start recognition. It continues to remain activated until a temperature-related engine speed is exceeded.
The higher the coolant temperature, the lower is the start quantity enable by the ME-SFI control unit.