thanks again for your replies
more info on the oxygen sensor relating to diesel engines would be appreciated
also did not know about the low pressure variable pump interesting
we had already changed the fuel pressure regulator not because we had seen a problem with it but because we had one, made as expected from testing no difference
as always this is going to vauxhall head office the two hours we have spent on it did not yield fruit which obviously makes us useless as opposed to the fact they have had it for 3 months
never mind I'm not bitter, i could spend the rest of my life in a futile attempt to fix this and not get paid for the hours spent or fix something i will get paid for
if i get any response back on this vehicle i will of course post the fix but as the vehicle is going back to vauxhall i don't know how truthful it will be
thank you again
graeme
ps this vehicle has 5000 miles on it