Looks like it pulled from the oil separator box. Its under the manifold so will require you to remove intake manifold. Its part of the pcv system that is likely clogged. Check ptc nipple at air pipe that goes to turbo down low past maf it has an electrical connector and 2 hoses attached to it. Takes...

Hose between the Charge Air Cooler (CAC) and the Idle Air Control (IAC) Valve, which is built into the intake manifold.

2001-03 | X40 Idle Control Valve Hose is Volvo Part Number 30637166.
$12.70 at FCP Euro.