A long time ago I had quite a few hesitation issues on my '12 Civic that were virtually all fixed by cleaning out the throttle body.

However a couple of weeks ago some similar hesitation/sluggishness issues came back. Checked my TB, looked good. Like before, I have no trouble codes but did notice my total fuel trim went to -12% while at idle.. not enough for a DTC but enough to get me thinking.

I pulled out each coilpack and noticed the one in cylinder 3 was covered in a light brown sooty "rust-like" material. I don't think it was rust, it just looked like rust dust. Some rubbed off on my finger but the coilpack itself looked like it had been stained it a shade of brown. It also smelled like gasoline. The coilpacks in the other 3 cylinders were fine.

I'm assuming this is a tell-tale sign of an improperly torqued plug that is allowing gas fumes to get up and contaminate the coilpack? Anyone see this before? I would imagine this has something to do with my issues.

I am due for new plugs in 5k miles (will probably do it sooner given this finding) so I will consider changing out the coilpack as well. Thanks

 

Is the spark plug crush washer in place and undamaged? 94