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The ME-SFI start quantity control function - GF07.61-P-3010V

ENGINE 273.961 in MODEL 216, 221 up to Model Year 8 

Shown on engine 272.963 in model 171 

Fig 1: ME-SFI Start Quantity Control Function Diagram
G07634014Courtesy of MERCEDES-BENZ USA

The start quantity control must guarantee the safe start of the engine. To do this, a decision is made as to whether this is a cold start, a warm start, a repeat start or a start following operation of the stationary heater.

In order to facilitate starting a cold engine, in addition fuel must be injected during the starting procedure, depending on the coolant temperature. The increased quantity of fuel injected is achieved by extending the injection time.

The start quantity control is dependent on:

The start quantity control is enabled after start recognition. It remains 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.

Component description for the ME-SFI [ME] control unit GF07.61-P-6000V 
Component description for the crankshaft Hall sensor GF07.04-P-6220V 
Component description for the coolant temperature GF07.04-P-6040V 
Component description for the hot film MAF sensor GF07.07-P-6000V 
Component description for the fuel injection valves GF07.03-P-6010V