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ME-SFI synchronizing fuel injection and firing order function - GF07.61-P-4009F

ENGINE 104.941 /943 /944 /991 /994as of 1.8.96 

ENGINE 104.995 

with CODE (494a) USA version 

with CODE (807) Model year 1997 

with CODE (808) Model year 1998 

with CODE (498) as of Model year 97 Japanese version 

ENGINE 111.921 /942 as of 1.9.98, 

111.943, 

111.944 as of 1.8.96, 

111.946 as of 1.6.98, 

111.947/973, 

111.975 as of 1.8.96 

ENGINE 111.945 

in MODEL 208.335/435 as of 1.6.98, 

202.020/080 as of 1.9.98 

ENGINE 111.974 

with CODE (494a) USA version 

with CODE (807) Model year 1997 

with CODE (808) Model year 1998 

ENGINE 112.910 /911 /912 /913 /914 /916 /917 /920 /921 /922 /923 /940 /941 /942 /943 /944 /946 /947 /949 /953 /954 /955 /970 /972 /973 /975 

ENGINE 113.940 /941 /942 /943 /948 /960 /961 /963 /965 /966 /967 /968 /969 

ENGINE 119.980 /981 /982 /985 

ENGINE 120.982/983 

ENGINE 137.970 

Shown on Engine 119 

Fig 1: Identifying ME-SFI Synchronizing Fuel Injection And Firing Order Function
G04605946
Fig 2: Ignition Firing Order Graph
G04605947

Task 

When the engine is started, defining the fuel injection order in line with the firing order on the basis of the signals supplied by the crankshaft position sensor and camshaft Hall sensor. In this way, enabling cylinder-selective cylinder shutoff and knock control system and optimizing emission levels.

Design/function 

When the crankshaft is rotating, an alternating voltage is generated in the crankshaft position sensor by the teeth of the driven plate. In this case, each tooth generates an alternating voltage signal.

No voltage is generated as a result of the gap created by 2 missing teeth. The ME-SFI control unit detects the TDC position of cylinder 1 and 6 or cylinder 7 and 12, respectively, with the 2nd negative slope after the gap.

If the signal from the camshaft Hall sensor is still at 0 V ("low") at this moment, the ME-SFI control unit processes this to detect ignition TDC of cylinder 1 and 7, respectively.

Synchronization of the fuel injection and firing order is further processed by the ME-SFI control unit for actuating the ignition coils and the fuel injectors. In addition, it is required for the anti-knock control and for the fuel shutoff at individual cylinders.

IMPORTANT

If no signal is received from the camshaft Hall sensor, the ME-SFI control unit determines the ignition TDC of cylinder 1 randomly.

Engine 111, 104 start about 1 second later.

Engine 119 starts if ignition TDC of cylinder 1 is determined correctly.

Engine may possibly start only at further attempt.

Engine Recognition of TDC position of cylinder Recognition of ignition TDC of cylinder
111 1 and 4 1
119, 104, 112, 113 1 and 6 1
120 Right cylinder bank: 1 and 6 Right cylinder bank: 1
Left cylinder bank: 7 and 12 Left cylinder bank: 7
137 1 and 7 Cylinder 1 (signal of camshaft Hall sensor right bank of cylinders "low")
  Crankshaft position sensor, location/task/ design/function   GF07.04-P-4116F 
  Camshaft Hall sensor, location/task/design/ function   GF07.04-P-4117F 
  ME-SFI ignition system signal assignment Engine 104 GF15.12-P-0001-02D
Engine 111 GF15.12-P-0001-02G
Engine 112 GF15.12-P-0001-02A
Engine 113 GF15.12-P-0001-02B
Engine 119 GF15.12-P-0001-02E
Engine 120 GF15.12-P-0001-02F
  Motor electronics control unit, location/task/ design/function   GF07.61-P-5000F