I asked the question already in the Vectra-C forum, but so far I have not received an answer to it (link to thread ) From a commonrail technique book I could actually only read out so much that a re-injection takes place only when a regeneration cycle of the DPF is initiated. An employee of a technical hotline said however, that there are also diesel engines, which carry out a re-injection under “normal” conditions. I had the latest engine management software installed by Opel. AGR, differential pressure sensor, charging pressure control valve were replaced, and the charging pressure sensor was cleaned. However, with a borrowed Gutmann tester I could observe the following values: 8mm3/Hub in idle mode and 60-70mm3/Hub in load mode without gl of course, if this is normal. Based on the fuel consumption, I would tap on something that is related to the DPF. But it actually looks quite good or the loading condition of the DPF changes regularly according to the tester, and according to the display about all 800km is burned free. What surprised me, however, is that the differential pressure showed no matter which loading condition -19mbar (60% loading u.a.) However, the sensor was replaced half a year ago, and the cables were checked for leak/permeability – all in all MfG eyewitnesses