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Intake air temperature correction function - GF07.61-P-4028F

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: Intake Air Temperature Correction Function (Shown On Engine 119)
G04738471

Task 

Reducing the thermal stresses on the engine at high temperatures.

Design/function 

The ignition timing point is retarded by the ME-SFI control unit in line with the intake air temperature (charge air temperature in the case of supercharged engines) and "load" (engine speed and air mass).

The ignition timing point is retarded only if the engine is operating at a high load and begins from an intake air temperature of approx. +35 °C and reaches its maximum at approx. +65 °C.

Example for full load:

35 °C → (retarded 3.5° crank angle)

45 °C → retarded 6.3° crank angle

65 °C → (retarded 9.5° crank angle)

The following information is processed in the ME-SFI control unit:

  Motor electronics control unit, location/task/design/function other than engine 111 EVO GF07.61-P-5000F 
  Engine 111 EVO   GF07.61-P-5000GS 
  Intake air temperature sensor, location/task/design/function   GF07.04-P-2100F 
  Crankshaft position sensor, location/task/design/function   GF07.04-P-4116F 
  Electronic accelerator/cruise control/idle speed control actuator location/task/design/function   GF30.22-P-4010F
  Throttle valve actuator, location/task/design/function Engine 111 EVO GF30.22-P-4101GS
  Hot film mass air flow sensor, location/task/design/function Engine 104, 112, 113, 137 GF07.07-P-4118G 
    Engine 111 (except engine 111 EVO)  
    Engine 111 EVO GF07.07-P-4118GS 
    Engine 119, 120 (round connector) GF07.07-P-4118E
  ME-SFI synchronizing fuel injection and firing order function   GF07.61-P-4009F 
  ME-SFI ignition system function other than engine 111 EVO GF15.12-P-0001F
    Engine 111 EVO GF15.12-P-0001GS
  ECI ignition system function Engine 137 GF15.15-P-3000L