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IFI fuel metering control function - GF07.12-P-3131-01H

Engine 605, 606 

Fig 1: Identifying IFI Fuel Metering Control Function
G04623960Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function with ignition "ON", engine running 

The IFI [ERE] control module (N3/7) uses a variable rectangular signal to actuate the coil (Y23/1a), which moves the magnet armature (Y23/1b) against the force of the return spring (20/3) towards the "START" or "FULL THROTTLE" position (a). The distance traveled by the magnet armature (Y23/1b) is dependent on the ratio of the on and off times of the rectangular signal. The maximum travel of the magnet armature (Y23/1b) and the control rod is 19.5 mm.

The longer the coil (Y23/1a) is supplied with voltage, the further the magnet armature (Y23/1b) is pulled into the magnetic field of the coil (Y23/1a). This control rod is thus forced to move towards "START"/"FULL THROTTLE".

After approximately 30 seconds, the return spring begins pushing the magnet armature (Y23/1b) back towards the "STOP" position.

Function with ignition "OFF", engine stopped 

The coil is not energized. The return spring (20/3) keeps the magnet armature (Y23/1b) and the control rod pressed in the "STOP" position (b).