Diagnosing Oil on Spark Plugs A Step-by-Step Approach

2013 2.5i Limited w/ 165k miles. What would be the most logical explanation for this? Piston rings? Spark plug O-rings? Valve covers? The fix is to replace the valve cover and the 6th gen covers don't have the oil leak issue while being a direct fit replacement. Liquid oil on a otherwise clean spark plug is a leak. Thick caked on carbon and traces of liquid oil would be a very worn engine. I changed all the plugs and noticed that cylinder had oil in it and the boot had oil on it to. Also white smoke is coming out of the exhaust. It's not a big deal but you do need to identify and correct the cause of the leak (needs plug tube seals and quite possibly the valve cover gaskets). The valve cover has a seal that goes around each spark plug tube. If that seal leaks you will get a slight amount of oil on top of the spark ... Oil can deteriorate sparkplug leads and the boot that goes over the insulator of the sparkplug. This can result in missfires. Spark plug tubes have o-rings that go bad , may want to tighten valve cover also. WHY THERE IS OIL IN SPARK PLUG WELL, ENGINE MISFIRE FIX If you have oil in spark plug well / oil in spark plugs well in this video we will ... While it may look like dirty oil, it isn't, this is unburnt fuel that all the lighter elements in the fuel have boiled off leaving the heavier ...