Base Engine Misfire with Excessive Oil Consumption (1)

Engine Mechanical - 5.3L L84 or 6.2L L87 | Diagnostic Information and Procedures | Document ID: 5003263 Base Engine Misfire with Excessive Oil Consumption Base Engine Misfire with Excessive Oil Consumption

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. Refer to Cylinder Leakage Test. 4. Repair or replace, as required.