1997 Buick Century Overheating?

I have a '97 Buick Century. I noticed the smell of coolant, and the “Low Coolant” light flashed on the dashboard. However, according to the temp gauge on the dashboard, the car was at normal temperature. I pulled over and opened the hood. The coolant in the overflow tank (not the radiator) was boiling, and sputtering out.

I took the vehicle to a nearby shop, where they said it needed a new “Coolant Level Switch.” They told me they put a new one in and did a coolant flush, charged me about $375, and sent me on my way.

About a mile down the road, the “Low Coolant Light” came on again. I pulled over and found that there was ZERO coolant in the engine. I filled it myself, and continued driving. Over the next few days, I checked the coolant every day and it stayed normal. I drove a bit, but never more than a few minutes, so the car didn’t have a chance to overheat.

Then, today, I drove it a good distance for the first time since the original incident. After a few minutes of driving, I smelled coolant and pulled over. The coolant in the overflow tank was once again boiling and bubbling out.

Any ideas what it might be?

If you were to bring this vehicle to me? My first suspect would be the intake manifold gaskets. After that? Head gaskets. Especially if it still has the Dexcool coolant in the system.

Tester