Q: 04 impala overheat changed waterpump n thermostat still overheat now stop running

At 200 thousand miles, the overheating could really be just about anything. But if you drove the car while it was overheating, there may have been some damage done that is causing your starting problem. Common causes of overheating are low coolant, bad thermostats, or a clogged radiator. Water pumps can fail, but that is not quite as common. A mild overheating problem caused by something like a bad radiator, if left to itself can eventually lead to a head gasket problem which will lead to starting and running problems. These things can be difficult to diagnose so you would do well to bring in a pro. You can do that conveniently by contacting YourMechanic. They can send a technician to your home or office to check out your Impala starting problem and your overheating problem and let you know what can be done for it.