Matrix2
Well-Known Member
I recently replaced the spark plugs on my 2006 Dodge 5.7 hemi with 65K miles. No drivability problems or smoke at all. Anyway, the spark plug nearest the firewall on cylinder 8 was coated with oil on the threads, the shell, the hex, and some on the bottom part of the porcelain. The other plug on no. 8 did not have any noticeable
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oil. Both are pictured (I wiped off some of the oil, but can still see the discoloration). For comparison is a picture of a plug from #6. There is no oil on the spark plug boots nor could I find any oil inside or outside the cylinder head cover. What could be causing oil to be on only one spark plug like this? I would have thought any oil getting into the cylinder would affect both spark plugs. Thanks guys!
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