Skip the auto shop - Our mechanics make house calls

Q: Plugs get oil on them and misfire

asked by on

The plugs in my car keep misfiring. For some reason, the plugs under the coil are getting oil on them. I was wondering what can cause this. My car has a North Star, 4.6-liter engine. Do you have any idea what the underlying issue is? Thanks.

The top most part of your engine is called the valve cover. On a V-shaped engine, you should have 2 valve covers. These valve covers are bolted to the top of the cylinder head and have gaskets in between the two mating surfaces to keep oil from leaking out.

In the center of your valve covers should be 4 holes in each one. These holes represent where the spark plugs are inserted into their sleeves. The valve cover gasket set comes with what are called spark plug tube seals which go around the sleeves to prevent oil from getting onto the spark plugs. These tube seals can go bad just like the valve cover gaskets can and will occasionally require replacement. Unfortunately, even if the valve cover gaskets are not leaking and the tube seals are, the valve cover gaskets will still have to be replaced as the valve covers will need to be removed to access the tube seals. I would recommend having this job performed by a certified technician for best results.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Spark or fuel problem with my engine.

If the engine will not turn over you most likely have a problem with either your battery or starter. I would enlist the help of a mechanic to check your battery and starter to find the culprit of why your...

Q: Bad misfiring issue - 2004 Nissan 350Z

Engine misfires can be caused by a list of problems, but there are a few suspects that occur more than others. Generally, misfires are caused by either a spark or fuel issue or in cases, a combination of both. Spark...

Q: Only get hot air in front

The front and rear blend doors are electronic actuators that will click when they are bad and cannot detect the position they are in. This is a very common problem and the front A/C and rear A/C can have different...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...