Looking at the photo, the plugs are as they came out of the engine. The upper left came from the left forward most cylinder etc.

I don’t think they look bad for the 90,000 miles. However the right rear plug is oily and when I pulled the coil/boot I could smell the oil.

The dealer did just replace the secondary air injection pumps, did a messy ass job, and it requires pulling the intake and the tech had dropped oil all over.

To be safe though, is that plug indicative of an issue? That rear plug and coil/boot doesn’t seem to have been removed so it’s hard to think the oil came from the bit maybe since the hex part of the plug has oil on it.

Thanks for looking!

From what i can see, those plugs look fine for 90,000 miles.

I’m with Power Surge, they look fine.

I agree. They appear to be fine.

Did you gap them. Those look like big gaps. When you say the plug is oily, you mean on the outside of the engine, where the lead connects to the plug? The electrode ends look good; a plug isn't considered oily until it's oily on the inside of the engine. Spill it on the outside, means nothing.

Spark pug color and condition tell you a great deal about what's going on in the engine; you do have one plug that's darker, but doesn't have deposits, and one plug that's clean enough it doesn't look like it was ever put in the engine. Clean to light brown is good; when you get wet looking plugs or dark plugs with buildup, you're often looking at leaking valve guides or worn rings, and sometimes a bad mixture.

Your plugs look clean, but check the gap, clean the threads and put a small dab of anti-seize one thread back from the end before screwing them in again. Don't use a wire wheel/brush for the end of the plug; bead blasting only, and then not in an iron-based media.

Gaps are .040, the one plug was new next to the dirtiest plug. There is oil on the threads.

I forgot the anti sieze so looks like I get to do it again.

Why is your new plug so much longer than your old plug? It's longer on both the threaded end and the other end, but the threaded end is more concern with the piston or valves.

The worst plug you can see the sheen. The other is the next forward plug.

The length is the same, gotta be perspective.

Thanks all!

quote:

Originally posted by Riley:
Gaps are .040, the one plug was new next to the dirtiest plug. There is oil on the threads.

I forgot the anti sieze so looks like I get to do it again.

The traditional method is to use a drop or two of oil on the threads, but if you don't pull plugs very often, it can end up being a glue. The anti-seize is there for the next time you pull the plug, so you don't take a helicoil with you.

No worries, I pulled them and added anti seize. Save me or the next owner some hassle.

If oil is getting in the spark plug recess and on the outside of the spark plug, the valve cover gasket - specifically the seal in the center of the cover around the hole - leaks.

Or oil was spilled on the engine, or the oil cap is loose or has a poor seal.

quote:

Originally posted by egregore:
If oil is getting in the spark plug recess and on the outside of the spark plug, the valve cover gasket - specifically the seal in the center of the cover around the hole - leaks.

The reason for the oil is covered in the OP