oily plastic pipe on top of motor!
 

I decided to replace the power steering cap o-ring as it looks like it has been leaking.
I also noticed the oily mess on this pipe near the AOS. (AOS was tested about 2500 miles ago and was OK.) Any ideas where this mess comes from or is it just normal dirty engine grime? Also what is this hard plastic tube for? (I wiped off part of it & that's why it looks clean/shiny).
Thanks.http://986forum.com/forums/uploads01...1422499724.jpg

Aha! I think I have answered my own question. It is the oil filler tube! I guess I may have a leak at the top or bottom. I think there are some o-rings I can replace.

Mine looked grimy too, before I replaced it while doing my coolant tank. But I couldn't find any evidence of any dripping. I think it was just general engine grime.

Yup, oil filler tube. They are famous for cracking in the "accordion" flex section. Not only does it get messy, but it also creates a vacuum leak that can lead to rough running and a CEL. Replace the whole pipe.

Thanks for the info. Replacing it sounds like a good idea. I hate having that messy area on an otherwise nice clean engine!
It looks like a pain to access.

It is a pain to access, particularly if it still has the spring clamps. Once you get it off, replace the clamps with screw-type clamps. Your knuckles will love you for it.

Mine was oily and I discovered that the engine side of the oil fill hose wasn't sealed properly. I assumed the mechanic that had recently changed the AOS wasn't careful enough when reinstalling it. I installed a new one just in case. Access is tough but the remote hose clamp pliers I saw written about on this forum made it so much easier.

just replaced mine last night, both the pipe (to the engine) and the tube (flex part to the trunk). the screw type clamp would be fine for the connection between the two parts, but for the connection to the trunk it would be hard to get in there to tighten.
I use this for the spring clamps:

I also didn't remove the intake as I have seen suggested several places. I removed the resonance tube and throttle. then removed the alternator to get to the second bolt.