Mine hasn't looked like that since, July 06
I've tried the pressure washed a bunch of times.. no luck for me
haha thanks, mine is about 15 months old too.
You are probably at the point of having to use some strong degreaser. Personally, this is what i would do.
-Get you some strong, enviro friendly degreaser
-Remove all the slightly removeable stuff. Intake hosing, engine cover, battery, fan shroud, etc. As much as you want to remove.
-Tape/wrap plasic trash/grocery bags over stuff not to soak, most notably, the fuse block on the drivers side, over the throttle manifold, etc.
-The wreak some cleaning havoc on that engine.
I haven't ever gone this far. But, after every trail run, i spend about 3 bucks on the body, and then about 5-8 on the undercarriage and engine bay. I am FAR FAR FAR from a neat/clean freak. But i know that a clean engine is a healthy engine.