Normal signs of a bad water pump are leaking from the weep hole, loose or wobbly belt pulley, or excessive noise from the water pump.
Overheating can be a sign of a bad water pump but there are a lot of other causes for overheating such as low coolant level or a dirty radiator.
Check for coolant around the water pump, particularly on the gasket or the weep hole. If you watch it with the car running, make sure there is no movement. Also try to feel the pulley for any play (NOT with the car running). The water pump on this car is on the timing belt, so it is critical that it is replaced before complete failure. If the bearing seizes, the engine could jump timing and bend some valves. If the water pump is suspect, replace it along with the timing belt, tensioner, and roller/idler.
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