Hi we have a Vectra, couldn't start it , then loads of black smoke it was the (excuse the girlie description) pipes that go on the injectors? under the cover? , these collapse, wont show on any diagnostics. i dont pay much attention to the Vectra ( give me a Triumph Herald and i can fix them) OH bought some pipe and it was fixed in 1/2hr, luckily the workshop where he works had had a few in with similar problems, so he could fix it straight away,
Other problem I had was the turbo hose blew off, just needed putting back on.