Oil in spark plugs


#1

Hi. '99 Escort ZX2 began really rough, stall at idle if at a long red light. Thought I’d throw in new spark plugs as the easiest quick-fix I could think of. My car’s a DOHC. When I pulled the first wire, it was dripping oil. Ultimately, we sucked out with turkey baster, wicked out with paper towels - about 1/2 cup, at a guess.

Put in the new plugs with fingers crossed. No help there. Still same problem. Any clue as to what would cause the oil in that area? The valve cover gasket was the only thing I could think of, but have never heard of it leaking inward.

What’s down there where the spark plug sits? How can I clean that out, assuming that there’s oil down in the spark plug “well,” and that may be causing the problem???




#2

There is gasket for the valve cover at the spark plug tubes. They are no longer sealing on your engine. You can pull the valve cover and get new seals or you can try cleaning it up and using a gasket maker of some kind.


#3

A valve cover gasket kit will come with 4 little round gasket-ettes that go around the spark plug holes. This is cheap and pulling off the valve cover is usually pretty simple. Go ahead and change all 4 of 'em and the main gasket too.


#4

Oh, and what’s down there where the spark plug sits is the cylinder and piston. If it is just oil in the hole (probably is), you can just take the spark plug out and let the oil drain in. Or if you want to play it safe you can dry it up with a rag.

Just to be clear, though, this is definitely a valve cover gasket leaking. There’s nothing else it could be.


#5

I had this problem months earlier. The mechanic change the valve cover gasket & the plugs. I went a step further & change the PCV valve myself just as a precaution. Several years before with another car , a mechanic friend told me it’s the PCV valve when I had oily (wet) spark plugs.


#6

Well, the PCV valve is supposed to relieve the pressure in the crankcase, so if its not working you have gaskets being subjected to pressure they aren’t really designed for, so your problem was probably bad valve cover gaskets caused or exacerbated by bad PCV valve.


#7

Couple of things you should do. First replace the valve cover gasket and seals. Second change the plug wires. Oil saturated plug wires will cause a misfire. Third change the PCV valve. After performing these repairs you can begin diagnosing the rough idle (if it still exists).
~Michael