Vectra Engine Stalling Rough Running

Sounds familiar. I've got a Vectra too, though it's a slightly different year. Had similar symptoms - check engine light, stalling, the works. Have you checked the fuel injector connections?

Could you elaborate on the specifics of the fuel injector connection issue you encountered? Were there any observable signs of damage or corrosion?

Yeah, on mine, the connector to the fuel pressure sensor was loose and corroded. Cleaning it helped for a while, but eventually, the problem returned. Ended up having to replace the connector. Honestly, after all that messing about, I would suggest a trip to the workshop to get it checked out properly.

Following your suggestion and an inspection, the issue was traced to a defective fuel pressure sensor cable. The cable and sensor have been replaced, resolving the symptoms. Total cost was 95€ Thank you again for your advice.