One of my sparkplugs is oily

[Synned]

One of my sparkplugs, the cylinder closest to the firewall drivers side was pretty oily when I pulled it, though I passed the cylinder balance test. Should I do a compression test just in case?

 

[dstanggt50]

You can do the compression test to see if the rings are alright, fi the compression test is ok, I would think you have a valve guide issue on that cylinder. Thats what happened when my valve guides went out.

 

[CManT1914]

A compression test is easy and fairly quick. I'd definitely do one. Remember, you're not looking for any specific number (although most peeps here get around 140-150), but rather you're gonna be looking at the difference between the cylinders. I think it's no more than 10 or 15% difference you want. So if cylinders 1,2,3,4,5,6,7 are 150, and cylinder 8 is 130, that's a problem.

 

[mo_dingo]

Yeah, and also a leak down test might be necessary as well.

But as for oil, one of your valves could be leaking (hopefully), so you might need to rebuild your heads, or get some aluminum ones.
Scott

 

[WhiteDevil]

Yeah a couple of mine did that with my stock heads. When i changed to my new ones that went away. Its probably valve seals.

 

[mo_dingo]

Yeah a couple of mine did that with my stock heads. When i changed to my new ones that went away. Its probably valve seals.

Yup, I just hope it's not a ring problem. But my guess is it's in the heads.
Scott

 

[Synned]

The car only has 52k miles. So would the compression still be bad on that cylinder if it was a valve seal? It would right

 

[mo_dingo]

The car only has 52k miles. So would the compression still be bad on that cylinder if it was a valve seal? It would right

Yes. the heads have to encase the 150psi buildup of pressure, and if they don't, your number will show lower than the rest of the cylinders.
Scott