Thaks for this idea and I'll double check but don't think that's the problem. A friend has also suggested the possibility that it may be coming from the Alternator which is water cooled! We'll check that too. One problem is that the noise only happens whilst on the move and never when ticking over so listening withg the bonnet up is a waste of time ;(

I have the same problem and only bought mine last week. It is going back to the car dealer tomorrow to see if they can try and fix it. I have researched the internet and got this information from a site in Holland from another Zafira owner with the same problem.

Changing the filter helps only a little if at all, but it seems to be caused
by the high position of the filter in relation with the tank and fuelrail.
If you lower the filter it seems to stop.

Please note I have only copied the above statement from the internet and do not know whether it actually works.

@bumpyball

We are in the same position - bought a 2011 Zafira 1.7 Ecoflex cdti a couple of weeks ago. So far it has been back to the dealer three times and the third time they took it to Vauxhall who said exactly what you were told - it is a 'characteristic of the car/engine' - not a fault.

This is a seriously weak response. It is obviously a fault and they should fix it. I don't like driving the car at all because of the noise which is a shame as we really like everything else about it.

Tomorrow I am going back to the salesman to try to get him to do something about it - if this fault can't be fixed I don't want the car.

Please let me know if your Dad can fix it but to be honest I don't think he'll have much luck.

Cheers