Buick Repair Questions? Ask a Mechanic for Answers ASAP
Here is what to do. Rent or borrow or purchase a coolant system pressure tester, get a large piece of clean cardboard, allow the engine to cool down, remove the radiator cap and top off the coolant, open up the cardboard and slide it under the vehicle in between the front two tires, far enough back that it is slightly behind the firewall and reaches out to just in front of the radiator, from side to side, then attach the cooling system pressure tester, pump up the cooling system to 15psi, then lay on the ground looking and waiting for the very first drip to hit the clean cardboard, then look directly above that and find the leak. The 15psi on the system will make it leak much worse and easier to find.
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