Oil in Plug Holes

[Larry Weil]

I recently changed the spark plugs in my 04 Impreza 2.5 TS Wagon. On two
of the plugs (not on the same side, actually diagonally opposite) there was
a fair amount of oil in the hole where the plug connector goes into the
engine. The plugs that I removed were fine, no sign of fouling, and no oil
on the threads. The car has approx 95,000 miles.

Does anyone have any idea what, if anything, this means?

Thanks for your help.

 

[ujduche]

There's a gasket between the valve cover and the tube that leads to the plug
galley. Spark plug galley gasket or something similiar. They tend to get
crushed or deform, which allows oil into the spark plug galley.

Sounds like you caught it early. The only time I've seen them fail was on a
99 2.5RS with about 60k miles.

 

[Todd H.]

I recently changed the spark plugs in my 04 Impreza 2.5 TS Wagon. On two
of the plugs (not on the same side, actually diagonally opposite) there was
a fair amount of oil in the hole where the plug connector goes into the
engine. The plugs that I removed were fine, no sign of fouling, and no oil
on the threads. The car has approx 95,000 miles.

Does anyone have any idea what, if anything, this means?

Welcome to my hell.

I'd had rough running in acceleration around 4000RPM that eventually
got bad enough to trigger a misfire code and check engine light,
found the dreaded oil on plug hole in the cylinder that threw the
code, diagnoses as leaking seals (either valve cover gasket or
other), then the question became "why's it doin that?" and
discovered a failing/blocking catalytic converter and (doh) the
dreaded 2.5L head gasket with a small breach.

$1800 at an independent and it's fixed though. Rebuilt heads with all
new seals, new head gasket, new cat.

Others have reported discovering oil and don't yet have any ill
effects though. You still under any warranty perchance? How's your
coolant usage? If it's used any coolant at all, get into the dealer
pronto and inquire as to why your car seems to be using cooland.
100k is only 5k away, and that's when they start scrutinizing head
gasket jobs a little more, I think.



Best Regards,

 

[Larry Weil]

There's a gasket between the valve cover and the tube that leads to
the plug galley. Spark plug galley gasket or something similiar.
They tend to get crushed or deform, which allows oil into the spark
plug galley.

Sounds like you caught it early. The only time I've seen them fail
was on a 99 2.5RS with about 60k miles.

Do I need to get this fixed? How big of a job is this? At this point,
I'll bring it to the dealer or a repair shop,as changing plugs is about the
limit of where I'm comfortable working myself.

Thanks again for your help.

 

[Larry Weil]

Others have reported discovering oil and don't yet have any ill
effects though. You still under any warranty perchance? How's your
coolant usage? If it's used any coolant at all, get into the dealer
pronto and inquire as to why your car seems to be using cooland.
100k is only 5k away, and that's when they start scrutinizing head
gasket jobs a little more, I think.

So far, no coolant use. Fingers crossed!

 

[Chicobiker]

Do I need to get this fixed? How big of a job is this? At this point,
I'll bring it to the dealer or a repair shop,as changing plugs is about the
limit of where I'm comfortable working myself.

I have a 2003 OBS and at about 100k kms I decided to try changing the
plugs myself. Found a little oil on both driver's side boots, but no
issues otherwise. Decided to wait. Now at 145k. Last time I looked
the boots were dry. Not sure what to think of this.

Had some hesitation issues for a short period of time, but the dealer
greased the spark plug wire connections and it went away.

I was gonna wait for the timing belt change and get the valve cover
gaskets done then, but the dealer says it won't save me anything. I
think I'm gonna wait and let them change the plugs next time around
and see if they try to sell me new valve cover gaskets.

Not sure what to suggest.