Engine Misfire Due to Oil in Spark Plug Tubes on Subaru Forester

Problem Description and Possible Solution

An oil leak can develop from the spark plug tube seals. Excess oil in the spark plug tubes can result in engine misfires and illumination of the Check Engine Light. Our technicians tell us that removing the valve cover and replacing the tube seals and cover gasket is necessary to correct this concern. Oil damaged spark plugs, ignition wires, and ignition coils will also require replacement.

Problem Data
RepairPal Verified
Average mileage: 107,950 (19,000–237,000)
Engine affected: 2.5L 4 Cylinder
12 model years affected: 1999, 2000, 2001, 2002, more2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
55 people reported this problem
Viewing 1 - 20 of 33 comments
just replaced the spark plug tube gaskets. Do it yourself, take your time, save yourself $500 vs dealer.
Pulled the boots to change the plugs and discovered oil all over them. New seals are on order now, looks like I've got another weekend project. I don't mind maintaining my vehicles but this is ridiculous! Why would Subaru allow for something like this to go on for so long???
Same story. Seems to have been fixed in a satisfactory manner,but I've owned 4 Subarus, and every one of them had oil leaks from seals, gaskets etc. Last time ever buying one of these.
I have the same problem with my car misfire Check engine light and the car stalking intermittent
Oil leaking into spark plugs. Am inquiring about how to get new tube seals and cover gaskets
Oil is leaking into spark plug area. No legitimate explanation for this problem. It will be a necessary and expensive repair. I am very dissatisfied with Subaru. I will likely buy a Toyota next time.
Worn out spark plug tube gasket and or valve cover gasket allowed oil to seep into spark plugs, which damages the spark plug wires. Needed to replace the spark plugs, wires, & gaskets.
Oil in Spark plug tubes. One more than others. Cleaned them out a little and ran better. Will get the seals done.
Went to change spark plugs and all sparkplug sleeves are leaking oil some more than others. Wiped down spark plug wires and installed new sparkplugs. Don't remember this with the 2002 Forester we had although I never changed plugs. Paid dealer outrageous amount for that service. Any idea what dealer would charge for the sparkplug tube gasket replacement?
Oil Leaked into Spark Plug Tubes causing misfire on Cyl 3,4. This was repaired then CC showed bad. After replacement of CC under warranty misfire problem is back. Dealer replacing Coil Pack (not under warranty).
Oil found in spark plugs when switching them. Changed valve cover gaskets and spark plug seals but now it runs rough.
Replaced valve cover gasket, spark plug gaskets, wires and plugs. Good as new.
Same exact problem. Was told there was a leak in the gaskets and getting onto spark plugs. He said the spark plug looked fine and wouldn't need replacing. Well, a month later the check engine light comes on and it's the spark plug and coil spring that went out. Car drives horrible now.
Oil leaked into spark plug tubes. Destroyed coil and wires. Replaced all.
Oil in my spark plugs trying to see if me needrd a oil pan gasket could be the problem
Replaced spark plugs, wires, and coil pack but check engine light is still on. When changing spark plugs they were covered in oil
Been having some minor engine misfiring and some buildup on the throttle body. Just discovered oil on spark plug wires. Likely valve cover gasket leak.
car died when i looked at my spar plugs they where coverd in oil
Same problem as all of the other comments, oil in plug tubes. 5th Subaru and 1st time I've ever had a problem with one... considering the miles I drive, not too bad to "fix" a problem, but shocked Subaru didn't have a re-call on this...
For the 60,000 mile service my mechanic noticed the issue. New gasket, plug tubes, wires and plugs were necessary.