Hey there. I'm slowly going crazy trying to find this.
From the engine crankcase, a hose runs to the airbox of the engine's air intake. The hose connects close to the back of the intake. The airbox/intake y-pipe also has a small hose that sticks off of it. The 2 hoses are connected via a nipple/barb connector.

Does anyone know the part number for this hose connector??? Or at the very least, maybe the size of one? Mine seems to have fallen out, and I absolutely cannot find it online anywhere after dozens of searches. The only place I've even seen it, is attached to y-pipes for sale on eBay.

You can see the connector in this listing's picture: y pipe fits 82mm throttle body m113k for e55 cls55 cl55 g55 s55 sl55 mercedes | eBay

https://www.fcpeuro.com/products/mer...mer-1130100382

is that what you are after? PN 1130100382

Thanks for the reply. Thankfully it's not that hose setup. Replaced one of those and it's awful.

The connector I need is the one that goes where the arrows are pointing. The hose I'm pointing at joins the airbox y-pipe of the intake.