I think only the newest generation of vaux/gm diesels shares the bits with fiat/alfa diesels.
e.g new astra sports/new corsa/new corsa van etc?
as for the older GM diesels, well, the cavalier age 1.7 was nasty, but tough as hell.
the newer ones 1.9/2.2 etc that found their way into saabs are best avoided. on th saab forecourt almost the entire forecourt (maybe 30-40cars) were the diesel varients. two salepeeps asked what I wanted, said they didn't have ANY petrol cars atall, just this fleet (ex fleet I reckon) of diesels and that their really good.
drove a 9-5 estate 2.2 tid (Cdti, same as), got about 10mins into a testdrive (stuck in traffic) temp gauge show'd medium, then it just stalled.
the Headgasket had instantously gone :bang:
SO I phoned the garage and asked where I was and they'd come with a pickup truck (test drive remember), I'd actually only gone 300-500yards
anyway, take your vectra back, and buy a TDci mondeo, boring yes, but they handle VERY well, have VERY VERY good engines, and you can pick em up for nothing now (esp with new model shoving prices down).