Owners of a 2009 Cadillac Escalade Hybrid equipped (built before 9-2-2008) with a 6.0L engine may complain of an engine misfire, oil consumption, and/or an SES light.
Upon inspection, oil deposits may be found on the #1 spark plug, which may cause #1 cylinder to misfire and set DTCs P0300 and/or P0301. This may be the result of excess oil splashing into the #1 cylinder wall due to a worn #1 cam bearing.
Inspect all of the spark plugs for oil fouling and cracks around the electrode porcelain.
If an oil fouled spark plug is found without an oil consumption concern, it may be the result of the cracked spark plug electrode. If cracked, replace the spark plug(s) and re-evaluate the misfire.
If the #1 spark plug is the only plug found with oil fouling and the electrode porcelain is not cracked, insect the related valve seals to ensure that they are not damaged or missing and repair as needed.
If the valve seals are fine, inspect the #1 cam bearing for possible cause of this concern.
The cam bearing can be replaced using part numbers from the catalog. If the cam bearing has spun, the engine will need to be replaced (or rebuilt).
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