What is the capped inlet on the late mode volvo power steering pump?

[TwoWheels]

There is an unused port on the steering pump of my 2006 Volvo 4.3GXi. What is its function, and could it be the source of air in my reservoir? The cap is on be seems to be a little oily.

Dave

 

[Jeepster04]

Re: What is the capped inlet on the late mode volvo power steering pump?

Ive also always wondered this. It has the PS cooler so its not a hook up for that.