So I was changing the spark plugs the other day on my car as I had a quite substantial missfire/ backfire issue and that was the cheapest place to start. The plugs looked terrible for 1 and the second cylinder plug was completely covered in oil which I know is either from the valve cover gasket not sealing or the spark plug tune gasket has failed. I've been searching everywhere to see if those seals are replaceable and haven't found anything so I'm wondering if they are even serviceable I just got the car and haven't taken the valve cover off yet to see I'd rather replace both while I have the cover off if at all possible and if it's not serviceable I have another idea to fix it that I've done on a past vehicle that worked like a charm with some RVT silicone. So my question is does anyone know if you can remove the spark plug tube seals, what they are made out of ( are they inset plastic or silicone / rubber ) and where I might be able to find replacements as every parts store I checked online said their seals won't won't fit the car ( I've only done compatibility checking haven't called the store yet) any help is greatly appreciated!!!