I have a 1986 ford ranger with a 2.9l in it. It keeps throwing up an (84) code which says the EGR Vacuum Regulator (EVR) circuit failure. I replaced the egr vacuum regulator and the egr position sensor but the code won't go away. What else could cause this code? I wasn't sure if the egr valve itself was connected to this code or if it was seperate. The tube that comes out of the bottom of the egr valve which I assume is supposed to go the the exhaust some how has been cut off. Can this cause the engine to miss while idling and cause that code to not go away. The tube has been discontinued by ford so don't know what to do if I need to replace it.

 

That tube is the problem. I have had the same proplem with my 99 Ranger and my 99 Taurus. There is a harness against the fire wall that runs behind the intake manifold. It has 3 of those vacume tubes in it (I belive they are red,green and white). There will be a connector the tube plugs into. Most likly it came out of the connector.
It is not super easy to find. It looks like a wire harness.