Bit of oil on spark plugs. Help please.

[01sapphirebob]

#286588

Pics for reference

[Shannon Whitehead]

#286598

The electrodes look pretty clean all things considered. Oil on the threads makes me think there might be some external oil seeping down onto the threads.

[Shannon Whitehead]

#286599

Looks about par for the course to me…do you have a catch can? What does the inside of your intake manifold look like? Greasy? Clean?

[01sapphirebob]

#286600

steve911 said:
The electrodes look pretty clean all things considered. Oil on the threads makes me think there might be some external oil seeping down onto the threads.

Ill double check and see if I notice any seepage from above the plugs

Steve M said:
Looks about par for the course to me…do you have a catch can? What does the inside of your intake manifold look like? Greasy? Clean?

I do not have a catchcan. I have heard that the GEN IVs get a lot of oil in the intake. Could this cause the oil on the threads?

[Florida04]

#286601

I had a leak once through the valve cover cap and left corner ( over cylinder 1-3-5 ) only when pushing the car. The cylinder head cover ( aka valve cover ) should be tightened to 95 inchpounds or 11 foot pounds.

[Shannon Whitehead]

#286606

01sapphirebob said:
I do not have a catchcan. I have heard that the GEN IVs get a lot of oil in the intake. Could this cause the oil on the threads?

There are many different avenues that oil can enter the combustion chamber…it can come in through the intake port itself (which a catch can would help prevent), it can come from a leaking valve stem seal, or it could possibly come from below if the rings weren’t doing a good job of sealing the bores. Start with the easy stuff first…all you have to do is pull a throttle body and look inside the intake manifold with a flashlight to determine how much oil is getting in through that avenue. If it is a fair amount, the inside of the manifold will likely look bronze in color and have a sheen to it. You’ll also see snail trails of oil coming out of the throttle bodies themselves…almost all of the Gen 4 throttle bodies I’ve seen (including mine) have had this, and indicates a need for a catch can.

[Shannon Whitehead]

#22685

So i started changing the spark plugs on my GEN IV tonight and as I was pulling them out I noticed a bit of oil on the plugs. What on earth could cause this?? I thought that maybe I overfilled the engine so i double checked the dip stick and it does appear to be a bit over the “safe” range. I always fill it up with 11 quarts per the manual. My mistake for not being more precise I guess. 🙁 I can’t remember if i have driven the car since I changed the oil in the fall. I changed plugs on cylinders 1,3,5 and they all appeared to have some oil on them.

I decided to change the plug as i did have some misfire codes last year and when i ran my car on the dyno one of the SRT engineers noticed a bit of black smoke and said you might want to change the plugs and wires since it looked like i was misfiring.

Any ideas, comments, suggestion are appreciated.

[Author]

Posts