In preparation for cleaning and adjusting the throttle body on my 179k 740-GL non-turbo wagon with a California emissions B230F engine, I removed the plastic air duct between the Mass Air Flow sensor and the throttle body. At the lowest level inside the accordion-pleated hose was about a 1/4" deep puddle of weird sticky gunk. It was sort of amber colored, about the consistency of wheel bearing grease, but much more sticky. Maybe a little like dried-up "No Smoke". No hint of similar gunk in the air filter box, the MAF sensor, or the throttle body itself, all of which were clean and dry. The oily, sticky goo was only in the bottom of the hose (the outside was sticky too). This is a new one on me? I've attacked the goo with driveway cleaner detergent, but it is really tenacious. I think that if I use a solvent powerful enough to remove the oily gunk, it will simultaneously eat the plastic, so I am going with repeated washing with hot water and powerful detergents.

Has anyone seen this before? ANybody know what the gunk is?
I would presume that the inside and outside of the air duct is supposed to be clean and dry.

Thanks