The valve cover gasket on my vehicle failed and let oil into the spark plug wells, coating the coil packs with engine oil How do I clean the oil residue from the coil packs without damaging them? Thanks for any ideas on this.
I’d just wipe them off with a rag or paper towel. If you feel like that wasn’t good enough, spray some carb cleaner on the rag and wipe them again.
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Thanks for the suggestions. I have both of those products. Never would have thought to consider electronics cleaner.
I’ve used a water-jet gadget (like used for teeth, waterpik, etc) filled w/ warm soapy water for simple cleaning jobs involving complex, tightly spaced, difficult to access surfaces. Since this is a high voltage coil, you’d have to thoroughly dry it afterward. Have to be careful not to spray any water forcefully into the electronics package.
I’d leave it alone. Oil is an insulator so it wont cause any harm. Some cleaning methods could actually cause harm by removing some dielectric grease added at the factory to protect the coils.
Engine oil in spark plug tubes will swell the COP boots or spark plug wire boots and can lead to coil failure or misfires… I would at least wipe them down…
I had a misfire on cylinder 2, which is why I started poking around and found the oil in the spark plug wells due to a brittle valve cover gasket I still had the misfire after cleaning the wells and coils. After swapping the coils on cylinders 2 and 1, and clearing the check engine codes, the car’s computer said the misfire was now on cylinder 1.
The vehicle is a 2005 Pontiac Vibe (rebadged Toyota Matrix) with 202,000 miles on it. Do I replace the one bad coil or all of them?
Replace all of the coils
At 202K miles, you’ve gotten your money’s worth
Good time to replace all of the spark plugs, as well
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Once the coil has failed for what ever reason the damage is already done (if you stab someone and then clean the knife off you still have the Stab wound)…
It is best to replace all the coils once they start failing, but if you can only budget the one then just remember the others have the same amount of use out of them and could fail at any time…
I hope you replaced the valve cover gasket w/tube seals (should be part of the gasket), if not you will be doing this again sooner then later…
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The car is fixed and runs good. I replaced all the spark plugs and coil packs with OEM Denso parts. As couple of you mentioned, the miles and age of the vehicle should be considered when replacing parts.
The car is still in all around good shape, so unless I stop to do the math I forget it is an 18 year-old vehicle. It is my college-age, now first-job daughter’s car. She has a 50 mile round trip highway commute to work, so it was worth the peace of mind to replace everything.
Glad to hear… You still have never mentioned if you replaced the valve cover gasket or not, you mentioned it was leaking bit nothing about replacing it, unless I missed it somewhere…
I replaced the valve cover gasket which included a replacement gasket for the spark plug wells. It was probably the original gasket, it was no longer pliable to the point of being brittle around the spark plug wells. I also found the o-ring on the timing chain tensioner had failed and was leaking oil. The timing chain had some slack in it, so I replaced the tensioner instead of just the tensioner o-ring.
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As mentioned above good idea to make sure the spark plugs are in good condition as part of this job. As the spark plugs wear w/use, becomes more difficult to make them spark, so computer raises the spark voltage, which places an extra burden on the coil, leads to early coil failure.
Might want to read all the reply’s George… 
I even quoted it in one of my reply’s, so it is their twice… lol
The manufacturer"s maintenance schedule for changing spark plugs is every 120,000 miles. The plugs in the car had 90,000 miles on them since the last plug change. The gaps on the plugs I swapped out had opened up quite a bit compared to the specified gap when new. They probably were putting a strain on the coils.
It looked like the coils were original to the car. I am not sure if coils are considered a wear item that should be routinely replaced based on age or miles. In this case, it seemed like a good idea to replace all of them.
Iridium tip spark plug gaps change very little in 120,000 miles. Did you install cheap spark plugs?
The flexible rubber air hose between the air box and the engine is probably not flexible anymore. If you haven’t replaced it already you might do that. I had to pull it off the air box to change the engine air filter on my 2005 Accord V6 and it was very difficult to get off and on after 10 years. No problem after installing the new one.
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They were Denso SK16R11 plugs
Thanks, I will check that. I have a 2000 Taurus that I maintain as a college car/first job vehicle for my son. The plastic and flexible components under the good in that car are very brittle. I kiddlingly wonder what part has cracked whenever the hood or a door is closed let alone bumps from road imperfections.
Those should be good quality plugs, presuming they really were made by Denso. I suppose they could have been counterfeit plugs though. What did the gap on the old plugs measure, compared to the new ones?
In any event it sounds like your car is running smoothly again. Good for you.