spiglet

I just bought a 97 glx 1.9 tdi galaxy and now I'm not so sure I should've (or at least not that one!). The battery light is staying on and there only seems to be 11.9 volts coming from the alternator when idling. Plus the steering feels slightly delayed and appears to be sticking very slightly ( but enough to make it awkward to drive in a straight line). Does anyone of you learned ford folk know what might be the problem? I like the car and would rather not have to put it through the window of the nice chap who sold it to me!!!!!