Originally Posted by Technical Ted
For the heating problem 1st check the coolant level in the radiator & see if there'* enough antifreeze in the coolant .
The electrical problems could be the alternator going. Your local auto parts store will usually check this for you.
If coolant is low in radiator then you need to find the source of the problem. You can clear air from the heater core by reving to 3000 rpm when the engine is completely hot (including the LOWER radiator hose) for 5 times. That'* from the 98 manual for LeSabre.
If there is air in radiator or heater, do you have a bleed valve on the thermostat housing to bleed out the last air that can get trapped due to the shape of the hoses to the radiator?
I'm interested in what you find here.