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Oil in Spark Plug Threads

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Daryl333

Daryl333

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Dry torque values are approximately 30% more than wet. So if it's truly something that was pre-doped, it's fortunate they didn't break off, especially when trying to remove them (over time as lube degrades or leeches it can cause a higher static friction trying to remove it).

Totally weird. I'd say that seems fishy (that someone outside the shop added lube to the threads) but what's more concerning is that the shop didn't have the experience/expertise to A) wonder why the threads are doped when every other plug you pull out of a box isn't and B) Recognize that wet torque values are different (maybe they did and adjusted accordingly, we can hope). Hopefully it didn't wreck your threads/tap in the aluminum head.

The good news (I guess) is that if it is true and it's lube that was on there, you don't have to worry about the seals on the valve covers or the other culprits to explain where it came from.
New Plugs are in with no complications so no worry about the head bore threads. And yea not having to worry about some seals or other part gone bad is a plus. The only reason I can think is that someone prelubed(?) the plugs returned them and they were sold as new.
And the shop did see the material on the threads and talked about the pros/cons of it and decided to install them. They should not installed them not knowing what the coating was and I WILL be letting them know that little tidbit.
I've been dealing with them for over 15 years and they do know what they're doing. But one did crack on install or removal.
(Flunky tech did the install) They are using a different guy on my car now. I will be having a more in depth conversation with them on Friday. And as said prior I did have a WOT misfire.
Haven't gone WOT yet but will Friday on the dyno cause I still haven't yet logged WOT for tuner.
So it looks we've dodged a bullet and hopefully the dyno session goes well.
And will see if NGK has an opinion on the plug pics I sent them.
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Unas2k5

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Are you asking me or have the wrong thread maybe?
My engine is a stock Gen 2 with approx 19,500 miles.
I read “Gen 3, 9lbs boost” so I thought you had a gen 3 block in a gen 2 like I do.
 
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Daryl333

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fmc_smt

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Looks to appear to have had anti seize installed at time of plug replacement
 

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Paul McWhiskey

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Seems to me that a small amount of anti seize is preferable to a spark plug seized in the hole. Of course, keep torque in mind when doing so. I have never used a torque wrench to install plugs, but I also don’t use any Ugg’s to tighten them. Never had one come loose or seize. I am talking many decades.
 

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When using anti-seize, be careful. Not too much, or near the tip and I always use the "nickle" permatex anti-seeze. As said Copper terrible, Aluminum not much better. First time I used copper, a couple plugs fouled with very low mileage.
 

diambo4life

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Hey...I used to work at an auto store. I think I have a very plausible reason why your spark plugs had anti seize or stuff on them. Another person SWAPPED THEM OUT OR RETURNED THEM to the store (after applying the lubricant) and the person doing the return just didn't care to open the boxes. They set them back on the shelf and they were resold to your mechanic. I have seen this happen more times than not. Your mechanic should have questioned it instead of just installing them in your car. That is troubling. No spark plugs come with lubricant pre-applied. Not. One.
 

Leigh_bullitt

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Just to let you know
I recently changed out my NGK plugs for some new ones and had exactly the same substance on my plugs.
The spark plugs wells are clean as a whistle and no issues with the engine at all. I’m guessing their is some kind of lubricant on those plugs.
 

Leigh_bullitt

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Should also add I had mine gapped badly to around 0,40 as well. Could always be an issue with the pcv valve.
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