Welcome to the forums, matey!
Did you get it off ebay or a trade ad on autotrader which you could link us to and we'll be able to give you more detail.
Being a 97 it's what we'd refer to as a D8 - It's a 406 before the facelift. There were two diesel motors at that time - a 1.9 8 valve, the XUD and a 2.1 12 valve. Both are reliable engines, don't get me wrong but the 2.1's fuel pump which is a Lucas suffers from some problems as opposed to the Bosch pump found in the 1.9s. As far as spec is conserned it'd help if you give us the trim level (eg. LX, GLX, Executive etc.) but beware as it varies substantially in pug world. You can find an LX with a changer like my old one and a GLX without one like my new one. Peugeot are.. difficult to understand sometimes
Some suffer from silly electric problems but that's mainly down to poor connections and wear and tear over time. Another thing to look out for is the front drop links - they are easy to replace but are all made of cheese (typical French, eh?). When you take it for a test drive go for a pothole or two (Don't tell the guy I told you that

) and listen out for any knocking noises infront. Good luck and I hope you've got yourself a minter, not a minger!
