An issue of note for any Astra's fitted with the 1.6 Ecotec engine Z16XER, in that I have had the misfortune to suffer an engine failure which totalled the engine on a dealer regular interval serviced car.

The fault starts as sounding like tappet clatter, but it isn't. Removal of the cam cover and inspection of the two camshaft cogs shows the design to be made up of a composite "dephaser" type device that adjusts the port timing the faster the engine turns as part of a DCVCP system. In this case the "dephaser" on the inlet camshaft went on starting the car on the drive and that was the end of that, this after only being run a few hours earlier. When severe and on it's way the engine sounds like a diesel running from cold, there are several example videos on Youtube ( https://www.youtube.com/watch?v=gIEBDfn4TBg ) but you may get advance warning of the failure in the form of a performance drop off.

The engine in my example was in the 63k miles bracket and just on 7 years old but if you have this engine fitted, and it's generic across the Vauxhall range as well as other marques, then get it checked. Since then I have heard of two further failures of this engine, one of which was in a Zafira.