Your 1998 Pontiac Grand AM W 2.4 liters keeps overheating You have already checked the thermostat radiator and water outlet Should you check water pump and timing chain next?
Check the compression. If you have one cylinder that is low, it
could possibly be a damaged head gasket that leaks into the coolant
jacket. When engines overheat the head tends to warp and the head
gaskets fail. If you want, you can purchase a test strip that will
tell you for certain if you have carbon monoxide in the coolant.
Carbon monoxide is the indicator that the head gasket is leaking.
If you've damaged the head gasket on ANY engine from overheating,
the only real option is to pull the head(s) and have the head
resurfaced then replace the head gasket. But before you do that,
check the coolant with the test strip.