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Discussion Starter #1
Allright, its a 94 tt with 102k miles.
Its running Mobil one 10w-30

Has anyone had oil on the spark plugs threads but no smoke or any other signs?

I recently changed plugs and when removing the 2nd cylinder it had oil on the threads. All of the other cylinders were fine. I replaced the crankcase hoses and put some NGK 3330 in. Since then i have had a sputter at idle and terrible gas mileage.

So today i did a compression check and came up with good numbers.

#1 180
#2 179
#3 180
#4 170
#5 166
#6 175

I also changed the plugs to NGK 2756 gapped at .41
The idle is smooth once again with these plugs.

My question is where could the oil be coming from? because its on the threads its coming from maybe a bad valve stem seal? Also, because i am not getting any smoke at idle and my comp numbers are good is this something i shouldnt really worry or spend a lot of money and time on? oh, and I have a blown 2nd, could any kind of oil be coming from that? I will be replacing the stock twins in the next week hopefully.. as much as i dont want to, i dont have the money for a single right now. :sad:
Thanks for any help/suggestions
 

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valve cover gasket

A slow leak will puddle up around your spark plug and run down the threads as you unscrew the plug. Same thing happened to me.
 
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Discussion Starter #3
I am pretty sure that is not it, there were no signs of oil puddling, it was rather dirty in there though.
 

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i agree........valve cover gasket would the first and cheapest and easiest place to start and more then likely your problem.and the washers for all the bolts that hold it down. Same thing happened to me . I started to get oil on a threads of 2 spark plugs. Try this first.
 

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King Ding-a-ling!
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I had the same problem... It turned out my valve cover gaskets were leaking as well! I polished them when I changed the gaskets! Cleaned everything up... and no more oil!
 
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