For 1990-2009 cars

Cause | Correction
--- | ---
Worn valves, valve guides and/or valve stem oil seals. |

1. Inspect the spark plugs for oil deposits. Refer to Spark Plug Inspection.
2. Repair or replace as required.

Worn piston rings. Oil consumption may or may not cause the engine to misfire. |

1. Inspect the spark plugs for oil deposits. Refer to Spark Plug Inspection
2. Inspect the cylinders for a loss of compression. Refer to Engine Compression Test.
3. Perform cylinder leak down and compression testing to determine the cause.
4. Repair or replace as required.