GF07.61-P-3007M Maximum Engine Speed Limitation, ME-SFI Function

GF07.61-P-3007M Maximum Engine Speed Limitation, ME-SFI Function

Component Identification:

Function
The ME-SFI control unit detects the engine speed from the signal supplied by the crankshaft position sensor. Engine speed is limited by shutting off the fuel injectors in the following conditions as a protection for the engine and the drive train:

1. Torque converter protection in selector lever position P/N
In order to protect the torque converter in selector lever positions P and N (no power transmission) from excessive static internal pressure, engine speed is limited to approx. 2500 rpm.

2. Limiting maximum engine speed when driving
In order to protect the engine from the consequences of impermissibly high rotational speeds, engine speed is limited to 6200 rpm and, after a further 10 seconds, to approx. 6000 rpm The drive mode is detected from the vehicle speed signal.

3. Safety fuel shutoff
In case of a defective throttle valve actuator, the actuation of the fuel injection valves is interrupted over approx. 1400 rpm. If the engine speed has dropped to approx. 1200 rpm, the fuel injection valve are actuated again (strong surging engine operation).