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so i changed my plugs and i noticed oil on the 3 to the right.the leftmost one was dry.i havent lost power that i have noticed tho, i was able to get up to 80 mph on the interstate like normal and was able to pass cars as well.
 

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you have a leaky valve cover. the oil is coming from inside the valve cover and leaking down into your spark plug holes. when you pulled the plugs out the oil gets all over the threads and down into the cyl's.
 

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haha see i told you more people would come up with stuff that I couldnt think of, if its leaking, just look into the spark plug well and see if you see any oil, just replace it, its a 30 dollar fix. I would do it to just avoid the burning oil smell if it ever hits the exhaust manifold.
 

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well it could sling all the oil out of the valve cover eventually causing the engine to run low on oil. but thats about it. just replace the gasket. we replaced the entire valve cover on my friends zetec. it was like 60 bux and came with the gasket already installed. it looks brand new now and took about 10 mins to install.
 

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get a new valve cover with gasket. it will give you the chance to do a little dress up too if you want.
 

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If it leaks enough, the oil can get in and foul your plugs.

Do these engines have O-rings around the spark plug boots where they pass into the valve cover? If yes, you want to replace as well those when you replace the valve cover gasket. I know this is an extremely common cause of oil on spark plugs in other cars (Subarus, specifically).
 

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> If it leaks enough, the oil can get in and foul your plugs

How would the oil "get in" to foul the plugs?
it cant foul the electrode but it can fill up the plug crevice and cause the spark to dissipate through the oil and the engine to misfire. also may cause a fire due to spark from the boot although its highly unlikely.
 

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Discussion Starter #14
turns out it needed a new valve cover gasket.i went ahead and installed some taylor wires since i have new plugs
 

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Sorry, didn't mean the business end of the plugs. I meant that if enough oil collected around the boots, they can short out. Poor choice of words with "foul."
 

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> I meant that if enough oil collected around the boots, they can short out.

Oil is an insulator.

Hydrocarbon lubricating oils have dielectric constants that typically range from 2.1 to 2.4, depending on the viscosity of the oil, the oil’s density, the relative paraffinic, naphthenic, and aromatic content and the oil’s additive package.

So Motor oil is more of an insulator than rubber, as quantifed by the dielectric constants:

RUBBER 3.0


RUBBER (CHLORINATED) 3.0

RUBBER (HARD) 2.8

RUBBER (ISOMERIZED) 2.4 - 3.7

RUBBER CEMENT 2.7-2.9

RUBBER CHLORIDE 2.1-2.7

RUBBER, RAW 2.1-2.7

RUBBER, SULPHURIZED 2.5-4.6
 

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Curious, I wonder what the conductivity of oil is after it has a few thousand miles on it? There's a fair bit of metal in the oil as it gets close to its change interval. Water is a good insulator too, until you add anything to it that isn't water.
 

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> There's a fair bit of metal in the oil as it gets close to its change interval.

No, there isn't.

The last oil analysis I did showed less than 100 PPM (Parts Per Million) of total metals in the oil.

If you are really interested in confirming this, try measuring the resistance of some used oil vs. some new oil with your multimeter.

P.S. Here is some info comparing new oil to used oi, and also the impact of ferrous contamination:

http://www.ijame.uz.zgora.pl/ijame_files/archives/v11PDF/n4/765-769_Article_05.pdf
 
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