Thanks Peter,
but I did the swap already, the new O2 sensors are in. But I did have the check engine light on for a while now and I had the code checked which was indicating a faulty oxygen sensor.
How can I reset the light and clear all error codes?

__________________
regards,
Sab.
'07 ML320 CDI (398 ft lbs / 1400 RPM)
'02CL 500
'91 928 GT Supercharged