Oil in Spark Plug Tube

Welp. When I recently replaced my spark plugs at about 65k miles, I found a very small amount of oil in the #8 cylinder. Upon inspection via bore scope, the leak was determined to be oil leaking through where the tube is press fitted into the cylinder head not from valve cover. Good thing I have extended warranty, it’s getting a new cylinder head sub-assy, about $8k of parts and labor. Lesson, do your preventative maintenance before any warranty expires.

 

So i am assuming you took it to the dealer had them look and they agreed without a fight? No BS lines about its normal or that you must have done something to get oil in there?

 

I’m actually the one that supplied the bore scope pix and video. My service advisor had no doubt and advocated for me. It did take 2 days to get approval from Toyota.

 

Gotcha, i guess that worked out as well as it could have.

 

Buy a powerball ticket b4 that luck goes south!!

 

Idk if I'd let my engine get torn apart to stop a little oil, but maybe I'm weird shove a paper towel down there once a year vs truck being down and hoping swapping heads is done correctly

 

Mine was leaking from same spot, different cylinder. After taking it apart to do the cam towers, I looked at it closely and determined it couldn’t come from there and had to be just from the cover seal. I’m surprised they wouldn’t try the seal first, before tearing it all apart. Either way yours will be fixed.

 

The passenger bank cyl head sub-assy was replaced. No replacement tube and seal available from Toyota.

 

Wow Toyota. I can't believe they won't have a simple fix for this. I have seen videos where they pull the tube out, apply some silicone and knock it back in.

 

Or sell the black seal shown in my pix. But I’m happy with new cylinder head sub-assy. I also kept the old part.

 

Yeah that would make sense. I just wouldn't be as happy as you, lol. My OCD doesn't let me be knowing that someone took apart a head and replaced it. I have no faith in dealers nowadays but that's just me. At least its getting repaired.

 

I’m the same. But the master tech from Lexus dealer came highly recommended. He took time to take tons of pictures for me. I inspected everything to find tooth comb and everything came back to the same place. I also had the valley cooling plate resealed and timing belt tensioner adjusted back to spec.