Help with Vacuum Control Valve

invalid@example.com (method0075), method0075
Fri, 28 Nov 2008 00:00:14 +0000

My 1992 e34 has a vacuum control valve between the valve head and the intake manifold. It sits below the fuel rail. I am concerned that it is not performing as it should and is allowing to much vacuum or too little. Can someone give me advice on this part. It is mechanical, not electrical like some e34s.

I am also finding it difficult to find a replacement for this part on line.

Before I get flamed I've been checking the web for this info but have turned up empty.