Whoa.... expensive problem... usually piston ring problem or worn. Maybe a compression problem too. Gas from the cylinder leaks thru the sides past the pistons into the engine oil area. Usually for vehicles with an extra huge number of miles on the clock, not the newer ones. Get second opinion...
I agree with Phil C. You need to have this checked and resolved quickly. Warm weather is near and gasoline mixed with overheated engine oil is a dangerous combination for you AND your car. Act on this soon!
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