Oil on spark plug
Oil on spark plug
Just did my first spark plug change and probably the only one done in a while.
I pulled both the 7 heat range plugs, first one out very black. Second one.....oily? Seems pretty oil covered it was also pretty loose too.
Any reasons as to why there's oil? Car runs good, only once its warmed up...
I pulled both the 7 heat range plugs, first one out very black. Second one.....oily? Seems pretty oil covered it was also pretty loose too.
Any reasons as to why there's oil? Car runs good, only once its warmed up...
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From: Australia
I second tightening them.
The blackness on the threads and electrode is semi-normal enough. But the blackness on the silver plug body (between the white porcelain and the threaded section) says maybe they were not tightened into the block enough.
That, or the rest of the outside of your engine is filthy black (?) and its gone onto the silver plug body too, over time
The thread and electrode is exposed to combustion area. The rest of the plug body is normally not (it is outside the block) unless a combustion leak from loose plug is escaping out and blackening the rest of the plug body.
Also, up near the hex, it looks oily wet. Anything dripping down the block from above? Oil filler neck leaking where it joins onto the block? Might pay to double check nothing is running down the side of the block onto the plug.
Make sense?
The blackness on the threads and electrode is semi-normal enough. But the blackness on the silver plug body (between the white porcelain and the threaded section) says maybe they were not tightened into the block enough.
That, or the rest of the outside of your engine is filthy black (?) and its gone onto the silver plug body too, over time
The thread and electrode is exposed to combustion area. The rest of the plug body is normally not (it is outside the block) unless a combustion leak from loose plug is escaping out and blackening the rest of the plug body.
Also, up near the hex, it looks oily wet. Anything dripping down the block from above? Oil filler neck leaking where it joins onto the block? Might pay to double check nothing is running down the side of the block onto the plug.
Make sense?
Last edited by SA3R; Jul 9, 2013 at 10:44 PM.
If what you're saying is that your front rotor, leading plug, has a lot of black buildup on the outside and that your rear rotor has a heavily 'sooted' plug then I believe you've melted a knock sensor and may just have a very rich/retarded tune.
I second tightening them.
The blackness on the threads and electrode is semi-normal enough. But the blackness on the silver plug body (between the white porcelain and the threaded section) says maybe they were not tightened into the block enough.
That, or the rest of the outside of your engine is filthy black (?) and its gone onto the silver plug body too, over time
The thread and electrode is exposed to combustion area. The rest of the plug body is normally not (it is outside the block) unless a combustion leak from loose plug is escaping out and blackening the rest of the plug body.
Also, up near the hex, it looks oily wet. Anything dripping down the block from above? Oil filler neck leaking where it joins onto the block? Might pay to double check nothing is running down the side of the block onto the plug.
Make sense?
The blackness on the threads and electrode is semi-normal enough. But the blackness on the silver plug body (between the white porcelain and the threaded section) says maybe they were not tightened into the block enough.
That, or the rest of the outside of your engine is filthy black (?) and its gone onto the silver plug body too, over time
The thread and electrode is exposed to combustion area. The rest of the plug body is normally not (it is outside the block) unless a combustion leak from loose plug is escaping out and blackening the rest of the plug body.
Also, up near the hex, it looks oily wet. Anything dripping down the block from above? Oil filler neck leaking where it joins onto the block? Might pay to double check nothing is running down the side of the block onto the plug.
Make sense?
Oil filler was a little on the wet side at the time. Cleaned it up.
It is possible that the knock sensor melted and dripped onto the plug although from what I've researched there's no oil in the knock sensor hole and it would be more of a goo.
Are you running higher than stock boost? If not, I'd stick with stock heat-ranges. Use a little anti-seize and torque to spec. Check them again in a few thousand miles and see what they look like.
I just bought it as four 9 heat range because that how Jason has it listed on his website as a set for sale. Lol, I'll do as recommended though. Thanks.
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