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 1,000 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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Plugs get oil on them and misfire

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: Rear and side lights malfunction

You may already know that your Audi has a sophisticated exterior lighting system that is computer controlled, monitors its own operation for faults, and communicates with other computer controlled systems on the car's network. This means that when it's time...

Q: Misfiring and burnt wires.

Hot starter wires are generally caused by a loose or contaminated contact at the starter or battery. These connections need to be cleaned and tightened to factory specifications. As far as the misfiring issue, the first step would be reading...

Q: Q: Hesitation when accelerating

There are a number of things that may cause the car to hesitate when accelerating such as low fuel pressure, a dirty or faulty mass air flow sensor, clogged or dirty fuel injectors, a faulty throttle position sensor or potentially...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.