1998 Buick Century engine oil

Are there drops of oil on ground after vehicle has sat in place for awhile? If so, place cardboard under vehicle and wherever the drips are at on the cardboard, try following it up under the vehicle to see where it is dripping from. It can run down from top of engine so it can be tricky to follow. Some obvious places to check are the main engine seal, oil filter and oil pan. If there is no visible leak then the oil may be leaking into the engine internally. This could be through the piston rings, valves, or head gasket. Remove your radiator cap, or look in your radiator fluid container. If it looks like a milkshake, then that would be your head gasket. When your car is running check the exhaust. If blue smoke is coming out, then that would be oil being burned out the exhaust.

Hope this helps.
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