01 grand prix gt 3.8L not super charged, I have replaced the thermostat sensor and thermostat,today because I thought that was the reason my temp gage was going up, well it turns out that was not the issue because my temp gage still wants to go up to the 250 mark. Is there any way to check to see if it might be my heater core, when I turn the heat on the gage drops down to the 170 mark or is it my radiator.
Sammie