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Oil leak into spark plug tubes?

24013 Views 63 Replies 10 Participants Last post by  Regulator
Ok I took my car to a shop to have it diagnosed. They couldn’t find anything wrong with my car other then it needs new seals where the spark plugs go in. They said cylinder 3 has a pretty bad leak. Could oil leaking into the spark plug tubes cause the car to miss, hesitate, and/or not want to start?
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Yes, if it gets bad enough. The oil will soak the plug wires. Buy a valve cover gasket set. It will come with new seals. Very simple deal.
So this oil leak could be causing all my problems? If so I hate my eclipse a little less lol.
Sometimes car will not want to start. Hesitation or like a very bad miss.
I also notice the spark plugs's tip are sort of white or very dry looking. The outer part near the threads have a thick black grim look.
This would not be your problem pertaining to your no-start condition. If it is bad enough it could cause a miss, yes. It's one of those I would have to hook the scanner up to and watch. Kind of hard to diagnose driveability issues over the internet.
Check engine Light comes on during the hesitation but does out after a few seconds of normal driving conditions.
Sometimes during the No start the car does feel like it is missing. Would one non firing spark plug cause it to not start or could the oil leak cause the coil pack to cut off?
The PCM will store that code History. Have a shop pull your history codes and we can go from there. Keep in mind your CEL does not have to be illuminated for the PCM to store a code. AutoZone's generic scanner can not pull codes from history. Find out the code(s) and let me now.
Thank you. I guess I shouldn't of reset my ECU before I took it to the local car shop her for the test.
I had this same issue, twice. Oil got past the valve cover seals and entered the spark plug tubes. That causes misfires, hesitation, etc and it can seem random. Mine happened more often in the lower RPMs. Each seal is $2 @ the dealer. I suggest replacing the valve cover gasket while you are at it. I would replace all 3 seals for each cover. Maybe start with the front and if that doesn't fix the issue then do the rear. The rear obvioulsy requires removal of the TB/manifold so do that last to avoid the hassle. :yesway: Replacing the front seals is a joke and shouldn't take more than 30mins total. You may want to search about removing a stiuck valve cover in case you run into that. Mine was a PITA to remove. Required a large rubber mallet, a 2x4, and brute strength. There area couple different methods posted for that on these boards. GL!
Thanks for your input. my hesitation/miss is at low rpms also or during deceleration and at idle after coming to a stop. Think I will do the entire valve cover gaskets and tube gaskets before I go back to the shop where they said everything was fine.
If the code is Misfire #3 p0303. I would lean towards a wire issue(oil soaked, etc).
I did NOT get spark plug seals when I bought a pair of valve cover gaskets. It can cause mis-fire, but I don't think it would keep the car from starting either -- except maybe on the 4-banger, where it would make more of a difference than on the 6.
Yea, the 4cyl valve cover gasket kit comes with the seals required to fix the problem. thank goodness its so easy on our motors. Other motors are not so easy to work on.
I did NOT get spark plug seals when I bought a pair of valve cover gaskets. It can cause mis-fire, but I don't think it would keep the car from starting either -- except maybe on the 4-banger, where it would make more of a difference than on the 6.
If you buy them from the dealer, they sell them separate. But FELPRO has a kit that you can get at auto stores for $40-50 that includes the vc gaskets and the spark plug tube seals.

And yes, as it has been mentioned before, oil leaks there cause missfire. I would most def fix that, and than see if you still have problems at startup.
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