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Home >> Volkswagen >> 1999 >> Golf Wolfsburg Edition, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 43 (1.8L - Fuel Injection & Ignition, Engine Code(S): AWD) >> 01 On Board Diagnostic (OBD) >> Measuring value blocks, evaluating, display groups 30-49, 99, 107 (oxygen sensor control) >> Measuring value blocks, evaluating, display groups 30-49, 99, 107 (oxygen sensor control) >> Display group 37 -oxygen sensor control- dwell time test

Display group 37 -oxygen sensor control- dwell time test

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Display group 37 -oxygen sensor control- dwell time test 
  • Engine running at idle
  • Control module in mode 04, basic setting
Read Measuring Value Block 37 ← Indicated on display:    
xxx % x.xxx V xxxx ms Text      
1 2 3 4 ← Display fields Specified value Evaluation
        Result (Test ON / Test OFF / sys. OK / not OK) Sys. OK  
      Dwell time of oxygen sensor regulator before catalytic converter -1200 to 1200 ms  
    Sensor voltage of oxygen sensor behind catalytic converter: 0.100 to 0.900 V Refer to Evaluation display group 36, display field 1 - sensor voltage of oxygen sensor behind catalytic converter 
  Engine load 12 - 30% ---

Note for display field 3: 

Oxygen sensor control behind catalytic converter is superior to oxygen sensor control before catalytic converter and is responsible for control correction. It corrects slight changes in the mixture (i.e. toward rich or lean) due to the oxygen sensor before catalytic converter by holding oxygen sensor control before catalytic converter at its higher or lower point for a specific time -t- (dwell time). If this time is in the positive range (i.e. 50 ms), mixture is shifted in the -enrich- direction. If this time is in the negative range (i.e. -50 ms), mixture is shifted in the -lean- direction. 

If value climbs to above 200 ms, this indicates a leaking exhaust system.