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Engine load states: check > < Check the Lambda probe's cables

Leon Mk2

Check mixture adaptation
Check mixture adaptation
–  Attach the unit -V.A.G. 1551- (-V.A.G. 1552-). Switch on the ignition and enter “direction code” 01 to select the engine control unit. (Fault finder: Connect and select the engine control unit → Vehicle diagnosis, testing and information system VAS 5051.)
   
Display reading:
–  Press buttons 0 and 8 for the function “Read the measurement values block” and confirm the entry with the Q button.
  
Rapid data transfer                 HELP
Select function XX
Display reading:
–  Press buttons 0, 9 and 9 for “Display group number 99” and confirm the entry with the Q button.
  
Read measurement values block       HELP
Enter display group number XXX
Display reading:
The Lambda probe's operating state is indicated in display field 4.
–  Check the operating state of Lambda regulation in display field 4:
  
Read measurement values block 99       →
         1         2         3         4
Meaning of the figures in the 8 digit numerical block for the Lambda regulator's operating state.
xxxxxxxxMeaning in case of digits = 1
1       Fault detected by self-diagnosis
 0      Not occupied
  0     Not occupied
   1    Lambda control limited dynamism, active
    1   Lambda regulator at limit
     1  Lambda regulator activated
      1 Lambda probe ready
       1State of mixture:
Message = 1: Rich mixture
Message = 0: Lean mixture

   
Display reading:
If the Lambda regulator is at the limit (indication for Lambda regulator at the limit at “1”), it can be determined through the mixture state indicator whether the Lambda regulator is at the limit of leaning or enrichment.
  
Read measurement values block 99       →
       1       2       3        XXXX111X
Display reading:
If the Lambda regulator is at the limit and the mixture state indication remains constant at “1”, it means that Lambda regulation has reached the limit with respect to “leaning”, however the Lambda probe continues to detect “very rich mixture”.
  
Read measurement values block 99       →
       1       2       3        XXXX1111
Display reading:
If the Lambda regulator is at the limit and the mixture state indication remains constant at “0”, it means that Lambda regulation has reached the limit with respect to “enrichment”, however the Lambda probe continues to detect “very lean mixture”.
  Note!
If the Lambda regulator remains at the limit for a certain time, either for “enrichment” or “leaning”, a fault is recorded in the fault memory.
–  If the Lambda probe functions perfectly, the self-adaptive Lambda values must be checked
–  Press the C button.
–  Press buttons 0, 1, and 1 for “display group number 11” and confirm the entry by pressing the Q button.
Mixture adaptation is subject to self-adaptation, that is, Lambda regulation detects differences between the engines (injector nozzle flow, compression, fuel pressure, etc.) and compensates for them by adaptation of the basic injection times programmed in the map of characteristics. Injection times are increased or reduced until a mixture with l = 1.
  
Read measurement values block 99       →
       1       2       3        XXXX1110
Display reading:
The value for Lambda self-adaptation at idling speed appears in display field 2.
t  Self-adaptive value positive (+...ms): basic injection time programmed very brief; the effective injection time ...ms longer in order to attain l = 1.
t  Self-adaptive value negative (-...ms): basic injection time programmed, very long; the effective injection time is ...ms shorter in order to attain l = 1.
The Lambda self-adaptation value at partial load is indicated in display field 3.
t  Values above 1: basic injection time programmed, very brief; effective injection time longer in order to attain l = 1.
t  Values below 1: basic injection time programmed, very long; effective injection time shorter in order to attain l = 1.
Theoretical values: → Vehicle diagnosis, testing and information system VAS 5051, Read measurement values block, display group 11.
  
Read measurement values block 11       →
         1         2         3         4

Engine load states: check > < Check the Lambda probe's cables