I'm not to sure what you mean about the power steering line, but the "bump" on the air bellows (that accordian looking black tube) from the air cleaner to the throttle body is probably not an open port, it's just there. Volvo has the idle control motor running off a line tapped directly from the air filter housing to the intake manifold, they still used the earlier air bellows, but didn't tap out this port. This "air line" was from the bellows to the intake manifold prior to this model. The heater control valve is in the lower heater hose in the engine bay, drivers side, near the throttle cable where it comes through the fire wall, unless someone has removed it. They were notorious for cracking and leaking, so maybe it has been taken out.