Knocking common in Buick Century
I looked at 2001 Buick Century with 72000 miles. Its got some rust on bottom of doors very clean inside guy wants 1500. It has a knocking sound. It drives good. Guy says had regular maintence.
If you are asking if a 'knock' from the engine is normal, NO.
Could be a rod knock, just walk away is your best bet.
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