I just picked up my gen2 liberty wagon great car so far and this is my second subaru. I was looking over the engine bay today and saw there is valve on the left hand side fuel rail, my problem is that the vacuum line that connects to this valve is snapped with about 12inch of vac hose still connected to the valve. I cant find any bare barbs on the motor, where should this valve be connected to?

Ok silly me found the barb on the manifold under the brake booster valve. Funny thing is, with the line replace and the valve plumbed back into the intake every time you start the car does the hi idle thing at 1100rpm then drop down a bit to like 1000rmp but then it keeps dropping to about 250 the idle then ossilates between 250 and 1000rmp till it peters out at 850rmp. I then tried disconecting it and starting the engine again, With the valve disconected the idle is fine, it starts 1100rpm then drops to 850.

 

For a start does anyone know the valve I am taking of? What does it do? Could that ossilation thing be the ecu relearning maps now the valve on the fuel rail is doing something?

 

Took it for a drive with it re-connected it feels fine, just the idle problem. Just a bit of a shock that reconnecting a valve which was disconected can make a engine idle like that.

that "valve" is the Fuel Pressure Regulator. it steals vacume off your manifold to work. maybe its (or the vacume line) is clogged?

How come when the fuel pressure regulator gets a vac signal the idle does that ossilation thing? The fuel pressure regulator on my car still holds a vacuum. How should I go about this, connect it and live with the strange idle? Or just plug the barb on the manifold.