Just got off the phone with Kia customer service regarding my 2012 Optima w/GDI engine w/119K miles, to report that the engine uses about 1 quart of oil every 100 miles approximately. I recently changed the spark plugs and PCV valve. One of the plugs appeared a bit gunky and the PCV valve was clogged. But otherwise, the engine seems to run very well. Other obvious symptoms is a black film on the rear of the car, and black smoke when I have to push the engine such as getting onto the highway. Anyway, other than assigning a case number, the rep said that since my car is out of warranty that there's nothing that Kia can do unless the engine siezes due to the infamous bearing issue. I thought I read in here that people had gotten new engines even with much higher mileage than my car due to excessive oil usage. Anyway, I'm looking for advice on what to do. Obviously, I need to go to a dealer and ask for an oil consumption test. Anything else I should know? How should I plead my case with the dealer? I've never had much favorable luck with dealer services and I don't want to wind up with a big waste of time and lots of aggravation. I appreciate and and all input.