I have a 2001 Bonneville SLE that is constantly overheating. I have replaced the water pump, the thermostat and the radiator cap and it continues to overheat. I took the top radiator hose off and started the car to see if water was circulating but it wasn't. Anyone have any ideas where to go next? The car has 170,000 miles on it and seems to run great until I got to this problem. I am new to the site and am desperately looking for some help with this issue. Any info would be great!

Thanks!

The coolant wont move until it'* up to temp. Let it heat up to operating temp and then see if it'* moving. Just be careful looking because the coolant is hot. There is a possibility your radiator core is plugged if it'* not moving.

In our cars once it'* started the water pump being belt driven circulates coolant. With the thermostat in what we call the closed position, it'* certainly not a much flow. There is flow though.

Was some work done on the car recently prior to the overheating issue? Sometimes an air bubble can develop in the system that is tough to get past. Many people fil through the thermostat hole before putting it in and sealing it up.

Some other ideas could be a plugged heater core or plugged radiator. Have you tried flushing water through the cooling system with only hose pressure and found it to flow through?

It wasn't worked on before the overheating started. I will have to try to flush it with water pressure and see if that works. I'll keep you posted.

Note, to look for the fans coming on as well when hot

The fan definitely comes on...