This Preliminary Information communication provides information to the technician about vehicles that have an engine misfire, oil consumption, and/or a Service Engine Soon Malfunction Indicator Lamp on. Technician may find Diagnostic Trouble Code P0300 and or P0301. Technician will need to inspect all of the spark plugs for oil fouling and cracks around the electrode porcelain. Technician will replace the spark plug if it is found cracked. If the #1 spark plug is the only spark plug that is oil fouled and the electrode porcelain is not cracked, inspect the related valve seals to ensure that they are not damaged or missing, and repair as necessary. If the valve seals are fine, inspect the number 1 cam bearing for possible cause of this concern. Replace the bearing if needed. If the cam bearing has spun the engine will need to be replaced.
