century 2003 overheating and heater throwing cold air

 

Simple diagnosis but maybe not:
1. Plugged radiator or heater core.
2. Thermostat bad, in backwards (new hoses connected wrong?)
3. Belt defective or slipping (probably a serpentine)
4. Water pump gone.
5. Coolant level way low.
6. Radiator fans not running.
Some areas would apply with one or the other, but both?

 

From your list a most likely cotender would seem to be the low coolant level.
Without actually being there to actually see the vehicle this is pure speculation .

 

It has been quite a while since I participated in this forum So I am guilty of neglect.
One thing I noticed was most folks that owned Buicks paid someone else to work on their vehicles. This is understandable with what GM has done to their cars.It is not only GM, other manufacturers have done the same thing and that is with the advancements in electronics and offered features there is less that you can do than ever before unless you have the equip and knowledge. The new Buicks are fun to drive , but expensive to own when repairs are necessary. Just about all we can do here is suggest possible alternatives and supply the towel after one has to cough up some hard earned cash to correct some of the problems with today's Buicks.
The older models had enough room under the hood to allow you to crawl in and go take a nap.Today's vehicles have so much jammed in the engine compartment you can't see the engine itself much less work in there.
So , I wonder how some of my past forum members are doing and do they still have their Buicks?

 

Roger that on overview Hanky with how it used to be and now. Yes, almost impossible to do anything on cars these days for sure. Would like to hear about Buick endeavors also and photos make a world of difference.