I have a 2002chevy impala 3.8 it's over heating but it's not showing on have and it sounds like water in the dash
air pockets ? low on coolant ?
Sounds like you're very low on coolant. The gurgling under the dash is air going through the heater core. With the engine cold and not running, remove the radiator cap and open the bleeder screw on the thermostat housing. Add coolant to the radiator until you have a steady stream of coolant coming from the bleeder screw. Close the bleeder screw and make sure the radiator is full to the very top. Put the radiator cap back on and fill the plastic coolant recovery tank to the full cold mark. If you find you have to fill the cooling system frequently you have a leak that needs to be fixed. Hope that helps! Jim