Several reasons could explain this high oil consumption:
* Worn Piston Rings: This is a very common cause of excessive oil burning. Over time, piston rings wear down, losing their ability to seal the combustion chamber properly. This allows oil to seep past into the combustion chamber and be burned.
* Worn Valve Guides or Seals: Worn valve guides or seals can also allow oil to leak into the combustion chamber.
* Leaking Valve Cover Gasket: While this wouldn't directly burn the oil, a leak would lead to oil loss and could contribute to the overall consumption, especially if the oil is leaking onto hot engine parts and burning off.
* Crankshaft Seal Leak: A leak from the crankshaft seal at the front or rear of the engine will result in oil loss.
* PCV Valve Issues: A faulty Positive Crankcase Ventilation (PCV) valve can cause excessive pressure buildup in the crankcase, forcing oil past seals and rings.
* Improper Oil Viscosity: Using oil that's too thin for the engine's operating temperature can lead to increased oil consumption. Always use the oil weight recommended in your owner's manual.
What to do:
Don't ignore this. Continued driving with excessive oil consumption can lead to serious engine damage. You should have a mechanic inspect your engine to diagnose the cause. They'll likely check for the above-mentioned problems, potentially using a compression test and a leak-down test to pinpoint the source of the leak or combustion chamber intrusion. Ignoring the problem risks catastrophic engine failure.
