'02 Lincoln LSE / 3.9L V8 (58,000 miles)
I have seen contradicting diagrams so I am not sure about the chamber number. I'm referring to the 2nd plug chamber on the left if looking at the engine from the front/grill.
I recently was changing my plugs after my "check engine" reported misfiring from "plug 4". Since I would be removing the valve covers already I was gonna change all the plugs. As I got to the above mentioned plug I found the chamber, plug and coil were wet with oil. None of the others had this problem. I've been told that the 3 most likely causes are:
1. worn head gasket seals
2. cracked head gasket
3. worn cylinder ring
Does anyone have an idea what might cause this? Or has anyone had this problem or similar? Any insight is appreciated. Thanks.
Okay... As the other guys said...
Now, I don't like doing it, but I'm going to have to help you out with part identification and terminology. What you are referring to valve covers as are actually called coil covers; It's that rectangular plate/cover that you removed to get to the coil on plug units and the plugs. That is not your valve cover, it is your coil cover. The item that it attaches to (which has the holes in it) is your cam cover (or valve cover; older terminology, but same thing). Where your spark plugs go... the hole in the cam cover... that's called your plug wells.
Now... I'm not ragging on you or anything, just trying to help you out. As for whoever gave you the idea's for the causes (the 1-3 you listed). They're not very familiar with engines I assume. The first one; "worn head gasket seal". This is not only poor explanation (a head gasket does not wear out, it fails), but also impossible. The spark plugs are installed into the head, the head to the block. The head gasket is between the head and block. So if it did fail, there still would not be any fluids anywhere near the plugs resulting from the head gasket failure. As for "cracked Head Gasket"... This is the same thing as the first; head gasket failure. But I'll assume cracked head is what was intended. VERY unlikely, but possible. Understand, there is about a square inch of surface area from the head that is in that plug well. Not only is it highly unlikely that a crack would find itself at that point, just out of the small amount of surface area, but this is also one of the single most unlikely places for a crack to develop on an aluminum head. Before a crack, you'd have an ejected spark plug... and you'd KNOW if that happened! And Last... "warn cylinder ring". This would only result in oil burn, poor idle and lack of power. The "cylinder ring", which is actually the piston rings act to seal the space between the piston and the cylinder. The spark plug in in the combustion chamber, which is open to the cylinder. However, there is a seal that is made when the spark plug is tightened; meaning if the cylinder filled with oil, it would still not result in a plug well filling with oil because that seal is still there between the plug and head.
I hope this explanation has helped a bit in your understanding of the situation.
Now, if you plan on replacing the cam cover gasket on your own, you'll need the KIT... they have a gasket, and a kit; the kit includes the seals for the plug wells. Just be sure you order the kit. Otherwise, if you take it in... I'm sure they'll know what the deal is.
