- Start a new session in ISTA D/+, perform the identification of the vehicle and a test:
2. Select DME and press ”Call up ECU functions”
3. In the DME menu choose the ”Diagnostics scan” section, ”Oxygen sensor control” subsection, select ”Signal, Oxygen sensor before catalytic converter” and ”Signal, Oxygen sensor 2 before catalytic converter”, press ”Read status”.
These data will show, with what fuel mixture the engine of your car runs:
- 1.99 .. 2.01V: Homogeneous mode; Lambda 0.99 .. 1.01
- 2.40 .. 3.00V; Stratified charge; Lambda 2 .. 3
- 2.25 .. 2.30V; Homogeneous lean; Lambda around 1.5
- 1.80 .. 1.90V: Desulfation of NOx catalytic converter
4. Fill the fuel tank at least 50%
5. Drive your car with a speed 110 .. 140 km/h at least 20 .. 30 minutes
6. During the Desulfation session monitor the parameters selected above. If Desulfation session begins:
- injection mode will remain Homogeneous and the voltage of the Lambda probe will drop below 1.90 V
- fuel consumption will be increased (up to 8 .. 9 liters/100km at 110 .. 120 km/h)
