I checked the car a bit and found the following:

- charcoal container is not connected any more (tube seems to be cut and draws vacuum under certain circumstances).

- Oxygen sensor signal looks ok, alternating between 0.2 and 0.7V, though there is a slow response to load changes. Alternating frequency about 1...2s at 1500rpm.

- EGR valve vacuum present.


I guess the HC value can brought below the limit by an oil change.

But I am worried about the NOX content. It looks like it is twice the max. I will check the EGR for clogging, but if that does not help I am clueless.

Any more ideas ?