I can't recall why this happens but this was in my '11 when I changed and in my brothers '12 when he changed plugs.

 

Valve covers or there is a rubber seal in the spark plug tube. Most likely that has cracked.

 

Thank you- I assume the valve covers have to come off to replace those seals?

 

Yeah, they would have to come off to replace them. Might as well replace the valve cover gasket as well.

 

Got the passenger side valve cover off, yeah the tube seals were rock hard. Surprisingly though the valve cover gasket was in great shape, still very supple. Was thinking of reusing it, but yeah I guess may as well replace it also.
The drivers side valve cover is scaring me. Looks like way less room to work over there, on the passenger side you can reach under the bottom frame rail to get to the lower cover bolts, doesn't look like that's the case on the driver's side.

 

2013 2.5i Limited w/ 165k miles. What would be the most logical explanation for this? Piston rings? Spark plug O-rings? Valve covers? Thx

View attachment 535354

check to see if the PCV valve is stuck open. remove it and give it the rattle test. Clean it as necessary or replace (torque to spec).

 

The driver side is made easier by removing battery, removing the 17 mm top nut for the engine/cvt mount on that side, remove the center bolt from the front mount under the crank pulley and jack up the engine on that side.

Don't use FelPro

 

Are there any brands you'd recommend in addition to a trip to the dealer?

 

Mahle is a perfect fit. Stone is OEM. Victor Reinz is also a perfect fit.

 

I bought it all from the dealership (see my other thread regarding parts counter vs online pricing)
Cardoc’s procedure above for doing the drivers side notwithstanding, for all the trouble I had squeezing that valve cover down into place on the passenger side and keeping the gasket affixed to the cover I’m probably going to take a pass on doing the drivers side myself where there’s even less room to work. (I also may have cross threaded one of the valve cover bolts on this one.) Valve covers on these boxer engines with the frame rail right where you need to work is a horrible job. I might just replace the plugs on the drivers side and call it a day

 

Did the part of the cover that you think has the stripped bolt get pulled in enough to seal it?

 

Yes it seemed to tighten fully, it was just really hard to turn in to the threaded hole. Could not finger turn it, backed it out a few times and tried again but same result so I ended up using a the ratchet, Made me think I crossthreaded
I drove the car today and checked under the car and around the cover for leaks and did not see anything, fingers crossed its all good