I have a few questions regarding 1991 190e 2.3. I am planing on buying one with 119K miles on it. It looks in pretty good shape. Locks don't work. When I rev the car up it smokes from or around the valve cover gasket area. I have a few questions, I hope someone can give me some feed back.
Thanks.

1. Are these cars long lasting?
2. Do they break down easily?
3. Are there common problems with these models?
4. When should the timing chain be replaced?
5. Are they reliable?
6. What should I look for?