I've got my spark plugs out today (to do a valve adjustment) and I noticed oil on the plug washers. The tips look ok, other than being a bit white (lean?), but there's oil up further on the plug and around the washer. There's also a bit of oil in the plug holes.

This is true for all 4 plugs. I've read about this being a valve cover gasket problem, but the gaskets appear (to me) to be ok. Perhaps I'm wrong.

Also, this may or may not be pertinent, but I've been getting a misfire CEL about once per month. All 4 cylinders, but never all at once yet. I'm attempting to diagnose that too, but that's a topic for another (already created) thread. I only mention it here in case it's related to the plug problem.

Any ideas on what this might be?

Thanks

 

The well seals (spark plug tube seals) are leaking. There are 4 pressed into the valve cover.

Somehow they were cut, or damaged during valve cover removal. It is rare for them to leak.

You don't have Krank vents correct?

The oil is shorting out the coils causing the misfire. Coils can be cleaned. Spray some brake-clean on a rag and wipe them inside and out.

 

Thanks for the reply. I'll have to replace the gaskets. The main one is starting to leak a bit as well, so it's time.

You are correct that I don't have Krank Vents. Should I? I've heard of them, but never really looked into it much. The car is stock, other than an exhaust, and I don't track it.

Also, where might I find brake-clean? Is this available at a normal autoparts store, or is there somewhere good online? Are there other alternative products?

Thanks again

 

billman,

have you heard of instances where the krank vents cause the seals to cause leakage into the spark plug chamber?

do you recommend krank vents, why or why not? I have them installed in my car, but have never inspected the spark plugs for leakage.

would oil on the spark plug washers be a problem?

 

I do not like krank vents, and I never will. They put undue stress on the well seals.

Thats a whole different story.

Brake cleaner is avail at any auto parts store. Any brand is fine.

 

would oil on the spark plug washers be a potential problem?

 

A small amount of oil on the spark plug washers is not a problem, but is a sympotom of an oil leak from the head past the well seals. If the spark plug gets wet enough with oil, it will start to misfire. Oil contamination of the coil-on-plug ignition system is probably not a good thing either. Both of these concerns are enough reason to make sure the well seals are in good condition.

I have seen two F20C engines with badly leaking well seals (one was my first S2000). In one case, the oil filled the well about half way up to the top. Needless to say, that is not a desireable condition.

 

thanks for the explanation coraldoc.

any word on krank vents and oil getting past the well seals due to krank vents putting undue stress on the seals?