There's a hose behind the engine that connects to some fitting that passes through the firewall on an old Volvo XC90 that seems to be leaking oil. I can't identify what that part is.
Does power steering fluid have any need to go past the firewall? What hoses and fluids can one typically expect to traverse the firewall of a vehicle?
Here's a portion of a video by another fella where this hose comes into view.