Oil in Spark Plug Wells

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What is involved in repairing ‘09 Highlander where #3 & #4 spark park wells have oil in them?
 
Riser tube seals?

They're separate components on some and part of the cam cover on others.
 
Just a guess but I'd imagine the valve cover gaskets are leaking or weeping. That'd not be a hard repair on some cars, but if it's the V6, the back side might be hard to get to.
Could definitely be something else but that'd be most likely, probably. Look for leaks first.
 
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On some older Toyota vehicles you have to press the tubes in the head. I have ordered new tubes and put sealer on them. Most of the time you can just replace tube seals in valve covers.
 
Originally Posted by Gebo
I was told I'd have to replace the heads.



I'd pull the valve covers off and see what's up.
 
Originally Posted by Gebo
I was told I'd have to replace the heads.


Some one a divorce pending or a large boat payment.
 
Originally Posted by user52165
Originally Posted by Gebo
I was told I'd have to replace the heads.


Some one a divorce pending or a large boat payment.

+1
I doubt Toyota would design something needlessly complex and labor intensive to rectify.
 
Guessing it's valve cover gaskets too, not enough information for more diagnosis.

Intake manifold - on the right inner fender the wiring harness bracket can be removed to allow the left hand to guide the socket, knuckle adapter, and extension down onto the difficult side bolt--from right hand coming from straight above. On the Sienna there is a brake type line at the firewall you can follow to find that bolt position, not sure how it is on the Highlander.

You also will likely want to remove the wiper cowel for more room, easy once you resigned to it.

The wiring harness is right down snug to the rear valve cover, and I really lack experience with the fasteners, so I figured the next spark plug change I might change the valve cover gasket being I have no issues. A few instructional video's out there, just watch several and it's probably a little easier on a Highlander.
 
Spoke directly with mechanic and he thinks the actually spark plug tubes have come loose from the head allowing the oil to come in. He spoke with another tech and they only give it a 30% chance that the gaskets will stop the oil from leaking into the spark plug wells.

I have never heard of such a thing.
 
This is possible. On my '99 Camry (if memory serves) there was a mistake on the tightening torque for the sealing nuts on the tops of the tubes (again, if memory serves, this is at least in part how the valve cover is held onto the cylinder head.... or it could be daughter no. 2's 2005 Corolla?)... The earlier specified torque was higher than the subsequently spec'd torque, thereby potentially loosening the tubes' fitment in the head).
 
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