21306-EA200

Yeah, that one.

I did my homework, asked around, read forum posts here, and spent quite a bit of time making sure I had everything needed to replace "while I was in there" - while doing my valve covers last month. I did a few other hard to reach hoses such as pcv, rocker cover to cover, swapped an ignition coil, cleaned every electrical connector, etc etc.

I have not seen this hose mentioned while myself and others have asked "while im in there, what should I do"

It is hiding underneath the intake, under the fuel rail, on top of the engine. It is about 3-4" long.
Trace the longer (passenger side) oil cooler hose up, to the hard line across the engine, which bends in and to 21306-EA200.

FOR THOSE OF YOU DOING INTAKE/VALVE COVER WORK IN THE Future
Get this hose and change it while you're in there.
I'm pretty pissed to say the least. I wasn't aware of this one, didn't see how while we were focused on the task at hand, and really wished I would've known about it. The thing is hard as a rock and damn it bothers me that it's not changed.

Just passing this along. Make this hose a sticky or something for Ukraine's sake