have a 99 Buick Century brand new radiator both hoses on tight new radiator cap and new waterpump still leaking coolant and over heating. any suggestions

My 94 same problem had to replace engine

I know it's a little late now but, i'm getting ready to fix that very problem myself. It's the Intake Gasket. It's a cheap part to buy but, and expensive fix. Ya, every time I move my car I have a large wet spot underneath it. "coolant" Yep, that's it! You have to keep a watch not to let your coolant run low/out or your engine overheat because ^^ Your engine will be ruined. So, I am keeping a close eye on it until I can afford to fix the problem.

mine was the same but the leak was blown intake gaskets which I've kept sealed up with Bars Leak intake sealer for 7 years because the gasket replacement is an expensive mostly pro only repair job. At first it didn't work long with anti-freeze so I tried it with plane water which worked good then I reintroduced some antifreeze for corrosion resistance as here in California I didn't often need freeze protection (in my car the leak filled up the front starter bolt hole and behind and below the head on the driver's side if you want someplace to look )