A ticking noise may develop from the engine due to a cracked exhaust manifold. Damaged exhaust manifolds will require replacement to correct this issue.
1991 Buick Century Problem Reports
Most Reported 1991 Buick Century Problem Reports
A coolant leak may develop from the water pump. The engine may overheat as a result of the coolant loss. A leaking water pump should be replaced.
Fuel injectors can short-circuit electrically causing a rougher than normal idle and reduced performance.