I recently bought my 91.....I had to replace the radiator.....common problem is the valve cover gasket leaking....check spark plug area for oil.....{cheap/easy fix though}

Other than those problems ....my 91 was ok....what i did, since i didnt know when last the timing was done although the belt was good I went ahead and did the following maintaince on it:

NEW Timing and balancer belts
New Water Pump
New seals and drive belts
New plugs/wires/filters