CHECK THESE NEXT:

6. DEFECTIVE TIMING CHAIN COVER GASKET
Have timing chain cover gasket professionally replaced.

7. CLOGGED CYLINDER HEAD OIL DRAIN HOLES
Remove engine sludge.

8. DEFECTIVE PUSH ROD COVER GASKET
Have push rod cover gasket professionally replaced.

9. WORN TIMING CHAIN OIL SEAL
Have timing chain oil seal professionally replaced.

10. HIGH ENGINE OIL LEVEL
Reduce engine oil level if necessary.