Skip the auto shop - Our mechanics make house calls

Q: Piston misfiring and oil on a sparkplug

asked by on

My car has a misfire on the 4th piston. I wanted to fix this myself so I replaced the sparkplugs. I found oil on a sparkplug. What caused this? Please give me some advice on what to check and fix the issue.

Oil in the spark plug bore is caused by a leaking valve cover gasket. This can short out the spark plug and cause damage to the plug and coil, and also the spark plug boot. The valve cover gasket set needs to be replaced to correct the issue. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the tools and training to replace the valve cover gasket for you.

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

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!

Get an instant quote for your car

Our certified mechanics come to you 銉籅acked by 12-month, 12,000-mile guarantee銉籉air and transparent pricing

Get a quote

What others are asking

Q: ABS + Brake + Traction Control Yellow Warning light

It depends on the nature of the faults. If there is a internal processing error or solenoid valve block assembly fault. Then it is likely the module will need to replaced and then programmed. A used module could be used...

Q: So I need a total tune up on my car! I was wondering if I could replace my spark plugs now and wait till next week to replace the coils?

Hi, thanks for writing in. Yes, that will not be a problem at all. If the coil is tested and is within spec there is no reason to replace it at all - I recommend using it. A fouled spark...

Q: BMW 528i 2000 (E39) fault codes P1523 and P1397

The vehicle should be inspected and diagnosed first hand but I can tell you broadly that if the seals on the VANOS system are original they should be replaced due to the age and mileage you are reporting. Camshaft position...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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.