ME-SFI idle speed control, function - GF30.22-P-0003AM

ENGINE 113.990 in MODEL 211, 219 

ENGINE 113.991 in MODEL 215, 220 

ENGINE 113.992 in MODEL 230 up to Model Year 2008 

ENGINE 113.993 in MODEL 463 up to 31.5.12 

ENGINE 113.995 in MODEL 230 up to Model Year 2008 

The throttle valve actuator controls the idle speed by altering the position of the throttle valve. It is actuated by the ME-SFI control unit.

To assist the idle speed control, the ignition angle can be retarded by as much as a 20° crank angle and advanced by as much as a 20° crank angle.

The ME control unit controls the idle speed in the warm-up phase and at different engine loads (e.g. drive position engaged, refrigerant compressor activated) according to the input signals.

Warm-up phase (heating speed) 

In order to bring the catalytic converter more rapidly to its operating temperature, the engine speed is raised from 1100 to 1300 rpm:

• at coolant temperatures < 40°C,
• after each starting procedure,
• during idling

for approximately 20 seconds.

After this time elapsed, the idle speed is increased at a coolant temperature < 70°C depending on the temperature for about 50 seconds by about 50 to 100 rpm.

Automatic transmission 

When a drive position is engaged, a lower engine speed is controlled in order to reduce the creeping tendency of the vehicle.

The information "Drive position engaged/not engaged" is transmitted by the ETC control unit via the CAN data bus to the ME control unit.

AC compressor 

Before connecting the AC compressor, the AAC control and operating unit sends a signal via the CAN data bus to the ME control unit to prevent a fall in the rpm at idle speed while connecting the AC compressor. The ME control unit upsizes subsequently the opening angle of the throttle valve.

Adjusting the ignition angle enables a faster response than adjusting the throttle valve.

The idle speed can be influenced with the STAR DIAGNOSIS.

	Crankshaft position sensor, location/task/design/function		GF07.04-P-4116AM
	Coolant temperature sensor, location/task/design/function		GF07.04-P-5026AM
	ME-SFI control unit, location/task/design/function		GF07.61-P-5000AM
	Ignition coils, location/task/design/function		GF15.10-P-3102AM
	Accelerator pedal sensor, location/task/design/function		GF30.20-P-4010HA
	Throttle valve actuator, location/task/design/function		GF30.22-P-4101AM