Oxygen Sensor Aging (Before Catalytic Converter) Testing

Oxygen Sensor Aging (Before Catalytic Converter) Testing

Special tools and equipment







- VAG 1788/10 Engine speed adjuster







- VAG 5051 and VAS 5051/1

Test requirement
- Coolant Temperature at least 80 degrees C.

Test sequence
- Connect the vehicle diagnostic, testing and information system VAS, Vehicle Diagnostic, Testing and Information System VAS 5051, Connecting and Selecting Functions and select the vehicle system "01 - Engine electronics" from the menu. When doing this the engine should be idling.







Display on VAS5051:
- Select the diagnosis function "04 - Basic settings" from the menu -1-.







Display on VAS5051:
1 - Enter display group
(figures up to 255)
- Using the keypad -2-, enter "034" to select Display group 034 and confirm entry with Q button.
- Set engine speed to 2000 RPM using VAG1788/10 RPM adjuster.







Display on VAS5051:
- Check readout in display zone -4-.

NOTE: This process can take a few minutes.







Note on display zone 2:
Value calculated from engine speed and engine load.

Note on display zones 3 and 4:
The dynamic factor signifies the oxygen sensor ageing. Decreasing dynamic factor indicates increased oxygen sensor ageing.

Further notes
If the readout in display zone 3 or 4 does not match the specification:
- Take car for a test drive to free oxygen sensor of any deposits, then repeat the test.

If the readout in display zone 3 or 4 still does not match the specification even after the test drive:
- Replace the heated oxygen sensor (HO2S) -G39-.