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Overheating/pinging protection function - GF07.61-P-4027F

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 111.943 /947 /951 /952 /955 /956 /957 /958 /973 /982 /983, 111.944 /975 as of 1.8.96, 111.946 as of 1.6.98, 111.921 /942 as of 1.9.98 

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: Overheating/Pinging Protection Function (Shown On Engine 119)
G04738467

Task 

Preventing engine damage resulting from excessively high coolant temperature.

Design/function 

If the engine temperature is too high, the ignition timing point is retarded by the ignition system as an overheating and pinging protection. Activation of the pinging protection correction begins at a coolant temperature of approx. 100 °C and is active only when engine is under load.

The ignition timing is retarded e.g.:

e.g.: 100° C and full load → 0° crank angle later

105° C and full load → 1.4° crank angle later

120° C and full load → 3.2° crank angle later

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

IMPORTANT The correction of the pinging protection and of the intake air are added together, a coolant temperature of e.g. 120 °C and an intake air temperature of 50 °C result in a maximum retardation of 11° crank angle at full load.

  Motor electronics control unit, location/task/design/function other than engine 111 EVO GF07.61-P-5000F 
    Engine 111 EVO GF07.61-P-5000GS 
  Coolant temperature sensor, location/task/design/function Engine 119, 120 GF07.04-P-5026F
    Engine 104, 111 GF07.04-P-5026G 
    Engine 112, 113, 137 GF07.04-P-5026A 
  Crankshaft position sensor, location/task/design/function   GF07.04-P-4116F 
  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