Boyfriend has a 16 Kia Optima with a 2.4 we’ve been together five years and I’ve changed the oil ever since we’ve been together. Last two oil changes were about 5 to 6000 miles each and was using Pennzoil platinum full synthetic 5W-30. Has no leaks but last oil change was 2 quarts low. And the oil change before that was 1 quart low inspected and found no leaks. Has 77 or 78,000 miles. Switched to Pennzoil full synthetic high mileage 5w20 because they had no 5W-30 hope to slow down the oil consumption, but the oil came out did not look good. He has 9 months left till it’s paid off and don’t wanna buy a car because we want to buy a house. I don’t think it started burning oil till the last two oil changes that I can remember.