* Worn Valve Stem Seals: These seals prevent oil from leaking down the valve stems into the combustion chamber. If they're worn or damaged, oil can seep past and burn during the initial startup, creating bluish smoke. The smoke is often more pronounced when the engine is cold because the oil is thicker and less likely to drain back down.
* Worn Piston Rings: Piston rings create a seal between the piston and the cylinder wall. If these rings are worn, oil can seep past into the combustion chamber and be burned. This is a more significant problem than worn valve stem seals.
* Leaking Valve Guides: Similar to valve stem seals, worn valve guides allow oil to leak into the combustion chamber.
* Oil Pressure Issues: Excessive oil pressure (less likely, but possible) could force oil past seals more readily.
It's crucial to get this checked out by a mechanic immediately. Continuing to drive with burning oil can cause significant engine damage, including:
* Scuffing of cylinder walls: The lack of lubrication from oil being burned will cause friction and damage to the engine's moving parts.
* Catalytic converter damage: Burning oil can foul the catalytic converter, leading to further expensive repairs.
* Complete engine failure: If left unresolved, this could lead to a total engine failure.
Don't delay getting your Chevy Metro inspected. The mechanic can perform a compression test, leak-down test, and visual inspection to diagnose the exact cause of the oil burning and recommend the appropriate repairs.
