As far as the oil light coming on goes. When you next drain the oil, remove the sensor and clean it off. That may do it, however if not, then it's reading the change in the sump when cornering too quickly and will probably need to be replaced. I had something similar with coolant level sensor. They are not the same but work on similar principle. Cleaned it up and it worked fine. May just have a bad ground or the sensor element is cruddy. Hope this helps..
1987 BMW 325