I have a 2000 Pontiac grand am 3.4l V6 that overheats?

[jeff]

I replaced the thermostat, replaced the water pump, and replaced the intake manifold gaskets. Still over heats. I removed the thermostat and left it out. Replaced the water pump again. still over heats. There is no warm air in the heater vents. There is no water in the oil. The exhaust is clear, no white or smoky exhaust. No signs of leaking. I replaced the upper radiator hose with clear tubing to see the coolant flow. No coolant flow is visible. I do not think water is ciculating thru the engine. It will idle without over heating, but as soon as you put it under load. It over heats.

 

[Chief High Commander, UAN]

Yeah that was a big thing with the Grand Am that style.
Try replacing the radiator, that was one of the biggest issues with it. Not the hoses, the actual radiator.
If nothing else works, take it over to a dealer and let them look at it.

 

[Zimgxp]

Did you get the correct rotation pump? Check the radiator fins for debris. Sounds like there could be an air pocket. Make sure you use the bleeder valves to purge the air out. If all else fails, could be a head gasket.