ME-SFI warming-up control, function - GF07.61-P-3022V

ENGINE 272.920 in MODEL 203 up to Model Year 8

ENGINE 272.922 in MODEL 211

ENGINE 272.940 in MODEL 203 up to Model Year 8

ENGINE 272.941 in MODEL 203 up to Model Year 8

ENGINE 272.942 in MODEL 171 up to Model Year 8

ENGINE 272.943 in MODEL 211, 219

ENGINE 272.944 in MODEL 211

ENGINE 272.945 in MODEL 251 up to Model Year 8

ENGINE 272.946 in MODEL 221 up to Model Year 8

ENGINE 272.960 in MODEL 203 up to Model Year 8

ENGINE 272.963 in MODEL 171 up to Model Year 8

ENGINE 272.964 in MODEL 211, 219

ENGINE 272.965 in MODEL 221 up to Model Year 8

ENGINE 272.966 in MODEL 230 up to Model Year 8

ENGINE 272.967 in MODEL 164, 251 up to Model Year 8

ENGINE 272.970 in MODEL 203 up to Model Year 8

ENGINE 272.972 in MODEL 211

ENGINE 272.975 in MODEL 221 up to Model Year 8

ENGINE 273.922 in MODEL 221 up to Model Year 8

ENGINE 273.923 in MODEL 164 up to Model Year 8

ENGINE 273.924 in MODEL 221 up to Model Year 8

ENGINE 273.960 in MODEL 211, 219

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

ENGINE 273.962 in MODEL 211

ENGINE 273.963 in MODEL 164, 251 up to Model Year 8

ENGINE 273.965 in MODEL 230 up to Model Year 8

ENGINE 273.967 in MODEL 209

ENGINE 273.968 in MODEL 221 up to Model Year 8

ENGINE 272.940 in MODEL 209

ENGINE 272.960 in MODEL 209

Shown on ENGINE 272

Fig 1: ME-SFI Warming-Up Control Function Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Fig 2: Enrichment Rate And Time Graph

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

After start and post-start enrichment the fuel-air mixture is further enriched by the warming-up control as part of the fuel-air mixture precipitates on the parts of the engine which are still cold.

An additional quantity of fuel is added to the engine by the ME-SFI [ME] control unit in line with the performance map.

As soon as it is enabled, the Lambda control monitors the enrichment rate.

At close to idle operation, the enrichment rate is mainly dependent on the coolant temperature at start. At partial load, the air mass is decisive.

The camshaft position determines the exhaust gas recirculation rate via the duration of the valve overlap. As the hot exhaust gases warm up the combustion chamber, the fuel vaporization changes and the enrichment rate must be tuned to match it.

The coolant is controlled by the three-disk thermostat in such a way that it is warmed as quickly as possible.

During warm-up, the ignition angles are determined from a particular performance characteristic.

The warming-up enrichment is dependent on:

Coolant temperature
Intake air temperature
Engine speed
Engine load
Idle speed/part load operation
Camshaft position
Correction programming with STAR DIAGNOSIS

Component description for the ME-SFI [ME] control unit		GF07.61-P-6000V
Component description for the coolant temperature sensor		GF07.04-P-6040V
Component description for the camshaft Hall sensor		GF07.04-P-6020V
Component description for the crankshaft Hall sensor		GF07.04-P-6220V
Component description for the hot film MAF sensor		GF07.07-P-6000V
Component description for the accelerator pedal sensor		GF30.20-P-2010V
Component description for the throttle valve actuator		GF30.20-P-2020V
Component description for an O₂ sensor	Component description for O₂ sensors upstream of TWC	GF07.04-P-6100V
Component description for an O₂ sensor	O2 sensors downstream of TWC	GF07.04-P-6100VA
Component description for the camshaft solenoid		GF05.20-P-2100V
Component description for the fuel injection valves		GF07.03-P-6010V
Component description for the valve three-disk thermostat		GF20.10-P-3160V