I have been using oil more than a quart during oil changes. I have had compression test done with no issues, no visible signs of leaks, and no other signs of burning oil ( white smoke, etc.). What could the issue be? Not sure if there could be sludge in the engine since I am not the original owner
My car has 127000 miles.
My car has an automatic transmission.
The only way that an engine can lose oil is to leak or burn it. I would recommend having the engine inspected for leaks to determine if any exist. If any leaks exist, I would recommend having them replaced. Common leak sources include the valve cover gasket, the oil pan gasket, and the rear main seal. If the engine is not leaking oil, it would be burning it. Common causes of burning oil are faulty piston rings or bad valve guide seals that allow oil to reach the combustion chamber. In order to verify whether these parts have failed, the engine will need to be partially or fully disassembled. I would recommend having all of these services performed professionally. If you would like, a certified technician from YourMechanic can come to your home or office to inspect your oil levels and search for leaks.
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